diff --git a/Objects/setobject.c b/Objects/setobject.c
index aaa4838..b35fef5 100644
--- a/Objects/setobject.c
+++ b/Objects/setobject.c
@@ -1,5 +1,5 @@
 
-/* set object implementation 
+/* set object implementation
    Written and maintained by Raymond D. Hettinger <python@rcn.com>
    Derived from Lib/sets.py and Objects/dictobject.c.
 
@@ -17,12 +17,12 @@
 static void
 set_key_error(PyObject *arg)
 {
-	PyObject *tup;
-	tup = PyTuple_Pack(1, arg);
-	if (!tup)
-		return; /* caller will expect error to be set anyway */
-	PyErr_SetObject(PyExc_KeyError, tup);
-	Py_DECREF(tup);
+    PyObject *tup;
+    tup = PyTuple_Pack(1, arg);
+    if (!tup)
+        return; /* caller will expect error to be set anyway */
+    PyErr_SetObject(PyExc_KeyError, tup);
+    Py_DECREF(tup);
 }
 
 /* This must be >= 1. */
@@ -35,20 +35,20 @@
 PyObject *
 _PySet_Dummy(void)
 {
-	return dummy;
+    return dummy;
 }
 #endif
 
-#define INIT_NONZERO_SET_SLOTS(so) do {				\
-	(so)->table = (so)->smalltable;				\
-	(so)->mask = PySet_MINSIZE - 1;				\
-	(so)->hash = -1;					\
+#define INIT_NONZERO_SET_SLOTS(so) do {                         \
+    (so)->table = (so)->smalltable;                             \
+    (so)->mask = PySet_MINSIZE - 1;                             \
+    (so)->hash = -1;                                            \
     } while(0)
 
-#define EMPTY_TO_MINSIZE(so) do {				\
-	memset((so)->smalltable, 0, sizeof((so)->smalltable));	\
-	(so)->used = (so)->fill = 0;				\
-	INIT_NONZERO_SET_SLOTS(so);				\
+#define EMPTY_TO_MINSIZE(so) do {                               \
+    memset((so)->smalltable, 0, sizeof((so)->smalltable));      \
+    (so)->used = (so)->fill = 0;                                \
+    INIT_NONZERO_SET_SLOTS(so);                                 \
     } while(0)
 
 /* Reuse scheme to save calls to malloc, free, and memset */
@@ -77,78 +77,78 @@
 static setentry *
 set_lookkey(PySetObject *so, PyObject *key, register long hash)
 {
-	register Py_ssize_t i;
-	register size_t perturb;
-	register setentry *freeslot;
-	register size_t mask = so->mask;
-	setentry *table = so->table;
-	register setentry *entry;
-	register int cmp;
-	PyObject *startkey;
+    register Py_ssize_t i;
+    register size_t perturb;
+    register setentry *freeslot;
+    register size_t mask = so->mask;
+    setentry *table = so->table;
+    register setentry *entry;
+    register int cmp;
+    PyObject *startkey;
 
-	i = hash & mask;
-	entry = &table[i];
-	if (entry->key == NULL || entry->key == key)
-		return entry;
+    i = hash & mask;
+    entry = &table[i];
+    if (entry->key == NULL || entry->key == key)
+        return entry;
 
-	if (entry->key == dummy)
-		freeslot = entry;
-	else {
-		if (entry->hash == hash) {
-			startkey = entry->key;
-			Py_INCREF(startkey);
-			cmp = PyObject_RichCompareBool(startkey, key, Py_EQ);
-			Py_DECREF(startkey);
-			if (cmp < 0)
-				return NULL;
-			if (table == so->table && entry->key == startkey) {
-				if (cmp > 0)
-					return entry;
-			}
-			else {
-				/* The compare did major nasty stuff to the
-				 * set:  start over.
- 				 */
- 				return set_lookkey(so, key, hash);
- 			}
-		}
-		freeslot = NULL;
-	}
+    if (entry->key == dummy)
+        freeslot = entry;
+    else {
+        if (entry->hash == hash) {
+            startkey = entry->key;
+            Py_INCREF(startkey);
+            cmp = PyObject_RichCompareBool(startkey, key, Py_EQ);
+            Py_DECREF(startkey);
+            if (cmp < 0)
+                return NULL;
+            if (table == so->table && entry->key == startkey) {
+                if (cmp > 0)
+                    return entry;
+            }
+            else {
+                /* The compare did major nasty stuff to the
+                 * set:  start over.
+                 */
+                return set_lookkey(so, key, hash);
+            }
+        }
+        freeslot = NULL;
+    }
 
-	/* In the loop, key == dummy is by far (factor of 100s) the
-	   least likely outcome, so test for that last. */
-	for (perturb = hash; ; perturb >>= PERTURB_SHIFT) {
-		i = (i << 2) + i + perturb + 1;
-		entry = &table[i & mask];
-		if (entry->key == NULL) {
-			if (freeslot != NULL)
-				entry = freeslot;
-			break;
-		}
-		if (entry->key == key)
-			break;
-		if (entry->hash == hash && entry->key != dummy) {
-			startkey = entry->key;
-			Py_INCREF(startkey);
-			cmp = PyObject_RichCompareBool(startkey, key, Py_EQ);
-			Py_DECREF(startkey);
-			if (cmp < 0)
-				return NULL;
-			if (table == so->table && entry->key == startkey) {
-				if (cmp > 0)
-					break;
-			}
-			else {
-				/* The compare did major nasty stuff to the
-				 * set:  start over.
- 				 */
- 				return set_lookkey(so, key, hash);
- 			}
-		}
-		else if (entry->key == dummy && freeslot == NULL)
-			freeslot = entry;
-	}
-	return entry;
+    /* In the loop, key == dummy is by far (factor of 100s) the
+       least likely outcome, so test for that last. */
+    for (perturb = hash; ; perturb >>= PERTURB_SHIFT) {
+        i = (i << 2) + i + perturb + 1;
+        entry = &table[i & mask];
+        if (entry->key == NULL) {
+            if (freeslot != NULL)
+                entry = freeslot;
+            break;
+        }
+        if (entry->key == key)
+            break;
+        if (entry->hash == hash && entry->key != dummy) {
+            startkey = entry->key;
+            Py_INCREF(startkey);
+            cmp = PyObject_RichCompareBool(startkey, key, Py_EQ);
+            Py_DECREF(startkey);
+            if (cmp < 0)
+                return NULL;
+            if (table == so->table && entry->key == startkey) {
+                if (cmp > 0)
+                    break;
+            }
+            else {
+                /* The compare did major nasty stuff to the
+                 * set:  start over.
+                 */
+                return set_lookkey(so, key, hash);
+            }
+        }
+        else if (entry->key == dummy && freeslot == NULL)
+            freeslot = entry;
+    }
+    return entry;
 }
 
 /*
@@ -159,50 +159,50 @@
 static setentry *
 set_lookkey_unicode(PySetObject *so, PyObject *key, register long hash)
 {
-	register Py_ssize_t i;
-	register size_t perturb;
-	register setentry *freeslot;
-	register size_t mask = so->mask;
-	setentry *table = so->table;
-	register setentry *entry;
+    register Py_ssize_t i;
+    register size_t perturb;
+    register setentry *freeslot;
+    register size_t mask = so->mask;
+    setentry *table = so->table;
+    register setentry *entry;
 
-	/* Make sure this function doesn't have to handle non-unicode keys,
-	   including subclasses of str; e.g., one reason to subclass
-	   strings is to override __eq__, and for speed we don't cater to
-	   that here. */
-	if (!PyUnicode_CheckExact(key)) {
-		so->lookup = set_lookkey;
-		return set_lookkey(so, key, hash);
-	}
-	i = hash & mask;
-	entry = &table[i];
-	if (entry->key == NULL || entry->key == key)
-		return entry;
-	if (entry->key == dummy)
-		freeslot = entry;
-	else {
-		if (entry->hash == hash && unicode_eq(entry->key, key))
-			return entry;
-		freeslot = NULL;
-	}
+    /* Make sure this function doesn't have to handle non-unicode keys,
+       including subclasses of str; e.g., one reason to subclass
+       strings is to override __eq__, and for speed we don't cater to
+       that here. */
+    if (!PyUnicode_CheckExact(key)) {
+        so->lookup = set_lookkey;
+        return set_lookkey(so, key, hash);
+    }
+    i = hash & mask;
+    entry = &table[i];
+    if (entry->key == NULL || entry->key == key)
+        return entry;
+    if (entry->key == dummy)
+        freeslot = entry;
+    else {
+        if (entry->hash == hash && unicode_eq(entry->key, key))
+            return entry;
+        freeslot = NULL;
+    }
 
-	/* In the loop, key == dummy is by far (factor of 100s) the
-	   least likely outcome, so test for that last. */
-	for (perturb = hash; ; perturb >>= PERTURB_SHIFT) {
-		i = (i << 2) + i + perturb + 1;
-		entry = &table[i & mask];
-		if (entry->key == NULL)
-			return freeslot == NULL ? entry : freeslot;
-		if (entry->key == key
-		    || (entry->hash == hash
-			&& entry->key != dummy
-			&& unicode_eq(entry->key, key)))
-			return entry;
-		if (entry->key == dummy && freeslot == NULL)
-			freeslot = entry;
-	}
-	assert(0);	/* NOT REACHED */
-	return 0;
+    /* In the loop, key == dummy is by far (factor of 100s) the
+       least likely outcome, so test for that last. */
+    for (perturb = hash; ; perturb >>= PERTURB_SHIFT) {
+        i = (i << 2) + i + perturb + 1;
+        entry = &table[i & mask];
+        if (entry->key == NULL)
+            return freeslot == NULL ? entry : freeslot;
+        if (entry->key == key
+            || (entry->hash == hash
+            && entry->key != dummy
+            && unicode_eq(entry->key, key)))
+            return entry;
+        if (entry->key == dummy && freeslot == NULL)
+            freeslot = entry;
+    }
+    assert(0);          /* NOT REACHED */
+    return 0;
 }
 
 /*
@@ -213,30 +213,30 @@
 static int
 set_insert_key(register PySetObject *so, PyObject *key, long hash)
 {
-	register setentry *entry;
-	typedef setentry *(*lookupfunc)(PySetObject *, PyObject *, long);
+    register setentry *entry;
+    typedef setentry *(*lookupfunc)(PySetObject *, PyObject *, long);
 
-	assert(so->lookup != NULL);
-	entry = so->lookup(so, key, hash);
-	if (entry == NULL)
-		return -1;
-	if (entry->key == NULL) {
-		/* UNUSED */
-		so->fill++; 
-		entry->key = key;
-		entry->hash = hash;
-		so->used++;
-	} else if (entry->key == dummy) {
-		/* DUMMY */
-		entry->key = key;
-		entry->hash = hash;
-		so->used++;
-		Py_DECREF(dummy);
-	} else {
-		/* ACTIVE */
-		Py_DECREF(key);
-	}
-	return 0;
+    assert(so->lookup != NULL);
+    entry = so->lookup(so, key, hash);
+    if (entry == NULL)
+        return -1;
+    if (entry->key == NULL) {
+        /* UNUSED */
+        so->fill++;
+        entry->key = key;
+        entry->hash = hash;
+        so->used++;
+    } else if (entry->key == dummy) {
+        /* DUMMY */
+        entry->key = key;
+        entry->hash = hash;
+        so->used++;
+        Py_DECREF(dummy);
+    } else {
+        /* ACTIVE */
+        Py_DECREF(key);
+    }
+    return 0;
 }
 
 /*
@@ -250,22 +250,22 @@
 static void
 set_insert_clean(register PySetObject *so, PyObject *key, long hash)
 {
-	register size_t i;
-	register size_t perturb;
-	register size_t mask = (size_t)so->mask;
-	setentry *table = so->table;
-	register setentry *entry;
+    register size_t i;
+    register size_t perturb;
+    register size_t mask = (size_t)so->mask;
+    setentry *table = so->table;
+    register setentry *entry;
 
-	i = hash & mask;
-	entry = &table[i];
-	for (perturb = hash; entry->key != NULL; perturb >>= PERTURB_SHIFT) {
-		i = (i << 2) + i + perturb + 1;
-		entry = &table[i & mask];
-	}
-	so->fill++;
-	entry->key = key;
-	entry->hash = hash;
-	so->used++;
+    i = hash & mask;
+    entry = &table[i];
+    for (perturb = hash; entry->key != NULL; perturb >>= PERTURB_SHIFT) {
+        i = (i << 2) + i + perturb + 1;
+        entry = &table[i & mask];
+    }
+    so->fill++;
+    entry->key = key;
+    entry->hash = hash;
+    so->used++;
 }
 
 /*
@@ -276,86 +276,86 @@
 static int
 set_table_resize(PySetObject *so, Py_ssize_t minused)
 {
-	Py_ssize_t newsize;
-	setentry *oldtable, *newtable, *entry;
-	Py_ssize_t i;
-	int is_oldtable_malloced;
-	setentry small_copy[PySet_MINSIZE];
+    Py_ssize_t newsize;
+    setentry *oldtable, *newtable, *entry;
+    Py_ssize_t i;
+    int is_oldtable_malloced;
+    setentry small_copy[PySet_MINSIZE];
 
-	assert(minused >= 0);
+    assert(minused >= 0);
 
-	/* Find the smallest table size > minused. */
-	for (newsize = PySet_MINSIZE;
-	     newsize <= minused && newsize > 0;
-	     newsize <<= 1)
-		;
-	if (newsize <= 0) {
-		PyErr_NoMemory();
-		return -1;
-	}
+    /* Find the smallest table size > minused. */
+    for (newsize = PySet_MINSIZE;
+         newsize <= minused && newsize > 0;
+         newsize <<= 1)
+        ;
+    if (newsize <= 0) {
+        PyErr_NoMemory();
+        return -1;
+    }
 
-	/* Get space for a new table. */
-	oldtable = so->table;
-	assert(oldtable != NULL);
-	is_oldtable_malloced = oldtable != so->smalltable;
+    /* Get space for a new table. */
+    oldtable = so->table;
+    assert(oldtable != NULL);
+    is_oldtable_malloced = oldtable != so->smalltable;
 
-	if (newsize == PySet_MINSIZE) {
-		/* A large table is shrinking, or we can't get any smaller. */
-		newtable = so->smalltable;
-		if (newtable == oldtable) {
-			if (so->fill == so->used) {
-				/* No dummies, so no point doing anything. */
-				return 0;
-			}
-			/* We're not going to resize it, but rebuild the
-			   table anyway to purge old dummy entries.
-			   Subtle:  This is *necessary* if fill==size,
-			   as set_lookkey needs at least one virgin slot to
-			   terminate failing searches.  If fill < size, it's
-			   merely desirable, as dummies slow searches. */
-			assert(so->fill > so->used);
-			memcpy(small_copy, oldtable, sizeof(small_copy));
-			oldtable = small_copy;
-		}
-	}
-	else {
-		newtable = PyMem_NEW(setentry, newsize);
-		if (newtable == NULL) {
-			PyErr_NoMemory();
-			return -1;
-		}
-	}
+    if (newsize == PySet_MINSIZE) {
+        /* A large table is shrinking, or we can't get any smaller. */
+        newtable = so->smalltable;
+        if (newtable == oldtable) {
+            if (so->fill == so->used) {
+                /* No dummies, so no point doing anything. */
+                return 0;
+            }
+            /* We're not going to resize it, but rebuild the
+               table anyway to purge old dummy entries.
+               Subtle:  This is *necessary* if fill==size,
+               as set_lookkey needs at least one virgin slot to
+               terminate failing searches.  If fill < size, it's
+               merely desirable, as dummies slow searches. */
+            assert(so->fill > so->used);
+            memcpy(small_copy, oldtable, sizeof(small_copy));
+            oldtable = small_copy;
+        }
+    }
+    else {
+        newtable = PyMem_NEW(setentry, newsize);
+        if (newtable == NULL) {
+            PyErr_NoMemory();
+            return -1;
+        }
+    }
 
-	/* Make the set empty, using the new table. */
-	assert(newtable != oldtable);
-	so->table = newtable;
-	so->mask = newsize - 1;
-	memset(newtable, 0, sizeof(setentry) * newsize);
-	so->used = 0;
-	i = so->fill;
-	so->fill = 0;
+    /* Make the set empty, using the new table. */
+    assert(newtable != oldtable);
+    so->table = newtable;
+    so->mask = newsize - 1;
+    memset(newtable, 0, sizeof(setentry) * newsize);
+    so->used = 0;
+    i = so->fill;
+    so->fill = 0;
 
-	/* Copy the data over; this is refcount-neutral for active entries;
-	   dummy entries aren't copied over, of course */
-	for (entry = oldtable; i > 0; entry++) {
-		if (entry->key == NULL) {
-			/* UNUSED */
-			;
-		} else if (entry->key == dummy) {
-			/* DUMMY */
-			--i;
-			assert(entry->key == dummy);
-			Py_DECREF(entry->key);
-		} else {
-			/* ACTIVE */
-			--i;
-			set_insert_clean(so, entry->key, entry->hash);
-		}
-	}
+    /* Copy the data over; this is refcount-neutral for active entries;
+       dummy entries aren't copied over, of course */
+    for (entry = oldtable; i > 0; entry++) {
+        if (entry->key == NULL) {
+            /* UNUSED */
+            ;
+        } else if (entry->key == dummy) {
+            /* DUMMY */
+            --i;
+            assert(entry->key == dummy);
+            Py_DECREF(entry->key);
+        } else {
+            /* ACTIVE */
+            --i;
+            set_insert_clean(so, entry->key, entry->hash);
+        }
+    }
 
-	if (is_oldtable_malloced)
-		PyMem_DEL(oldtable);
-	return 0;
+    if (is_oldtable_malloced)
+        PyMem_DEL(oldtable);
+    return 0;
 }
 
 /* CAUTION: set_add_key/entry() must guarantee it won't resize the table */
@@ -363,42 +363,42 @@
 static int
 set_add_entry(register PySetObject *so, setentry *entry)
 {
-	register Py_ssize_t n_used;
+    register Py_ssize_t n_used;
 
-	assert(so->fill <= so->mask);  /* at least one empty slot */
-	n_used = so->used;
-	Py_INCREF(entry->key);
-	if (set_insert_key(so, entry->key, entry->hash) == -1) {
-		Py_DECREF(entry->key);
-		return -1;
-	}
-	if (!(so->used > n_used && so->fill*3 >= (so->mask+1)*2))
-		return 0;
-	return set_table_resize(so, so->used>50000 ? so->used*2 : so->used*4);
+    assert(so->fill <= so->mask);  /* at least one empty slot */
+    n_used = so->used;
+    Py_INCREF(entry->key);
+    if (set_insert_key(so, entry->key, entry->hash) == -1) {
+        Py_DECREF(entry->key);
+        return -1;
+    }
+    if (!(so->used > n_used && so->fill*3 >= (so->mask+1)*2))
+        return 0;
+    return set_table_resize(so, so->used>50000 ? so->used*2 : so->used*4);
 }
 
 static int
 set_add_key(register PySetObject *so, PyObject *key)
 {
-	register long hash;
-	register Py_ssize_t n_used;
+    register long hash;
+    register Py_ssize_t n_used;
 
-	if (!PyUnicode_CheckExact(key) ||
-	    (hash = ((PyUnicodeObject *) key)->hash) == -1) {
-		hash = PyObject_Hash(key);
-		if (hash == -1)
-			return -1;
-	}
-	assert(so->fill <= so->mask);  /* at least one empty slot */
-	n_used = so->used;
-	Py_INCREF(key);
-	if (set_insert_key(so, key, hash) == -1) {
-		Py_DECREF(key);
-		return -1;
-	}
-	if (!(so->used > n_used && so->fill*3 >= (so->mask+1)*2))
-		return 0;
-	return set_table_resize(so, so->used>50000 ? so->used*2 : so->used*4);
+    if (!PyUnicode_CheckExact(key) ||
+        (hash = ((PyUnicodeObject *) key)->hash) == -1) {
+        hash = PyObject_Hash(key);
+        if (hash == -1)
+            return -1;
+    }
+    assert(so->fill <= so->mask);  /* at least one empty slot */
+    n_used = so->used;
+    Py_INCREF(key);
+    if (set_insert_key(so, key, hash) == -1) {
+        Py_DECREF(key);
+        return -1;
+    }
+    if (!(so->used > n_used && so->fill*3 >= (so->mask+1)*2))
+        return 0;
+    return set_table_resize(so, so->used>50000 ? so->used*2 : so->used*4);
 }
 
 #define DISCARD_NOTFOUND 0
@@ -406,112 +406,112 @@
 
 static int
 set_discard_entry(PySetObject *so, setentry *oldentry)
-{	register setentry *entry;
-	PyObject *old_key;
+{       register setentry *entry;
+    PyObject *old_key;
 
-	entry = (so->lookup)(so, oldentry->key, oldentry->hash);
-	if (entry == NULL)
-		return -1;
-	if (entry->key == NULL  ||  entry->key == dummy)
-		return DISCARD_NOTFOUND;
-	old_key = entry->key;
-	Py_INCREF(dummy);
-	entry->key = dummy;
-	so->used--;
-	Py_DECREF(old_key);
-	return DISCARD_FOUND;
+    entry = (so->lookup)(so, oldentry->key, oldentry->hash);
+    if (entry == NULL)
+        return -1;
+    if (entry->key == NULL  ||  entry->key == dummy)
+        return DISCARD_NOTFOUND;
+    old_key = entry->key;
+    Py_INCREF(dummy);
+    entry->key = dummy;
+    so->used--;
+    Py_DECREF(old_key);
+    return DISCARD_FOUND;
 }
 
 static int
 set_discard_key(PySetObject *so, PyObject *key)
 {
-	register long hash;
-	register setentry *entry;
-	PyObject *old_key;
+    register long hash;
+    register setentry *entry;
+    PyObject *old_key;
 
-	assert (PyAnySet_Check(so));
+    assert (PyAnySet_Check(so));
 
-	if (!PyUnicode_CheckExact(key) ||
-	    (hash = ((PyUnicodeObject *) key)->hash) == -1) {
-		hash = PyObject_Hash(key);
-		if (hash == -1)
-			return -1;
-	}
-	entry = (so->lookup)(so, key, hash);
-	if (entry == NULL)
-		return -1;
-	if (entry->key == NULL  ||  entry->key == dummy)
-		return DISCARD_NOTFOUND;
-	old_key = entry->key;
-	Py_INCREF(dummy);
-	entry->key = dummy;
-	so->used--;
-	Py_DECREF(old_key);
-	return DISCARD_FOUND;
+    if (!PyUnicode_CheckExact(key) ||
+        (hash = ((PyUnicodeObject *) key)->hash) == -1) {
+        hash = PyObject_Hash(key);
+        if (hash == -1)
+            return -1;
+    }
+    entry = (so->lookup)(so, key, hash);
+    if (entry == NULL)
+        return -1;
+    if (entry->key == NULL  ||  entry->key == dummy)
+        return DISCARD_NOTFOUND;
+    old_key = entry->key;
+    Py_INCREF(dummy);
+    entry->key = dummy;
+    so->used--;
+    Py_DECREF(old_key);
+    return DISCARD_FOUND;
 }
 
 static int
 set_clear_internal(PySetObject *so)
 {
-	setentry *entry, *table;
-	int table_is_malloced;
-	Py_ssize_t fill;
-	setentry small_copy[PySet_MINSIZE];
+    setentry *entry, *table;
+    int table_is_malloced;
+    Py_ssize_t fill;
+    setentry small_copy[PySet_MINSIZE];
 #ifdef Py_DEBUG
-	Py_ssize_t i, n;
-	assert (PyAnySet_Check(so));
+    Py_ssize_t i, n;
+    assert (PyAnySet_Check(so));
 
-	n = so->mask + 1;
-	i = 0;
+    n = so->mask + 1;
+    i = 0;
 #endif
 
-	table = so->table;
-	assert(table != NULL);
-	table_is_malloced = table != so->smalltable;
+    table = so->table;
+    assert(table != NULL);
+    table_is_malloced = table != so->smalltable;
 
-	/* This is delicate.  During the process of clearing the set,
-	 * decrefs can cause the set to mutate.  To avoid fatal confusion
-	 * (voice of experience), we have to make the set empty before
-	 * clearing the slots, and never refer to anything via so->ref while
-	 * clearing.
-	 */
-	fill = so->fill;
-	if (table_is_malloced)
-		EMPTY_TO_MINSIZE(so);
+    /* This is delicate.  During the process of clearing the set,
+     * decrefs can cause the set to mutate.  To avoid fatal confusion
+     * (voice of experience), we have to make the set empty before
+     * clearing the slots, and never refer to anything via so->ref while
+     * clearing.
+     */
+    fill = so->fill;
+    if (table_is_malloced)
+        EMPTY_TO_MINSIZE(so);
 
-	else if (fill > 0) {
-		/* It's a small table with something that needs to be cleared.
-		 * Afraid the only safe way is to copy the set entries into
-		 * another small table first.
-		 */
-		memcpy(small_copy, table, sizeof(small_copy));
-		table = small_copy;
-		EMPTY_TO_MINSIZE(so);
-	}
-	/* else it's a small table that's already empty */
+    else if (fill > 0) {
+        /* It's a small table with something that needs to be cleared.
+         * Afraid the only safe way is to copy the set entries into
+         * another small table first.
+         */
+        memcpy(small_copy, table, sizeof(small_copy));
+        table = small_copy;
+        EMPTY_TO_MINSIZE(so);
+    }
+    /* else it's a small table that's already empty */
 
-	/* Now we can finally clear things.  If C had refcounts, we could
-	 * assert that the refcount on table is 1 now, i.e. that this function
-	 * has unique access to it, so decref side-effects can't alter it.
-	 */
-	for (entry = table; fill > 0; ++entry) {
+    /* Now we can finally clear things.  If C had refcounts, we could
+     * assert that the refcount on table is 1 now, i.e. that this function
+     * has unique access to it, so decref side-effects can't alter it.
+     */
+    for (entry = table; fill > 0; ++entry) {
 #ifdef Py_DEBUG
-		assert(i < n);
-		++i;
+        assert(i < n);
+        ++i;
 #endif
-		if (entry->key) {
-			--fill;
-			Py_DECREF(entry->key);
-		}
+        if (entry->key) {
+            --fill;
+            Py_DECREF(entry->key);
+        }
 #ifdef Py_DEBUG
-		else
-			assert(entry->key == NULL);
+        else
+            assert(entry->key == NULL);
 #endif
-	}
+    }
 
-	if (table_is_malloced)
-		PyMem_DEL(table);
-	return 0;
+    if (table_is_malloced)
+        PyMem_DEL(table);
+    return 0;
 }
 
 /*
@@ -525,223 +525,223 @@
  *     }
  *
  * CAUTION:  In general, it isn't safe to use set_next in a loop that
- * mutates the table.  
+ * mutates the table.
  */
 static int
 set_next(PySetObject *so, Py_ssize_t *pos_ptr, setentry **entry_ptr)
 {
-	Py_ssize_t i;
-	Py_ssize_t mask;
-	register setentry *table;
+    Py_ssize_t i;
+    Py_ssize_t mask;
+    register setentry *table;
 
-	assert (PyAnySet_Check(so));
-	i = *pos_ptr;
-	assert(i >= 0);
-	table = so->table;
-	mask = so->mask;
-	while (i <= mask && (table[i].key == NULL || table[i].key == dummy))
-		i++;
-	*pos_ptr = i+1;
-	if (i > mask)
-		return 0;
-	assert(table[i].key != NULL);
-	*entry_ptr = &table[i];
-	return 1;
+    assert (PyAnySet_Check(so));
+    i = *pos_ptr;
+    assert(i >= 0);
+    table = so->table;
+    mask = so->mask;
+    while (i <= mask && (table[i].key == NULL || table[i].key == dummy))
+        i++;
+    *pos_ptr = i+1;
+    if (i > mask)
+        return 0;
+    assert(table[i].key != NULL);
+    *entry_ptr = &table[i];
+    return 1;
 }
 
 static void
 set_dealloc(PySetObject *so)
 {
-	register setentry *entry;
-	Py_ssize_t fill = so->fill;
-	PyObject_GC_UnTrack(so);
-	Py_TRASHCAN_SAFE_BEGIN(so)
-	if (so->weakreflist != NULL)
-		PyObject_ClearWeakRefs((PyObject *) so);
+    register setentry *entry;
+    Py_ssize_t fill = so->fill;
+    PyObject_GC_UnTrack(so);
+    Py_TRASHCAN_SAFE_BEGIN(so)
+    if (so->weakreflist != NULL)
+        PyObject_ClearWeakRefs((PyObject *) so);
 
-	for (entry = so->table; fill > 0; entry++) {
-		if (entry->key) {
-			--fill;
-			Py_DECREF(entry->key);
-		}
-	}
-	if (so->table != so->smalltable)
-		PyMem_DEL(so->table);
-	if (numfree < PySet_MAXFREELIST && PyAnySet_CheckExact(so))
-		free_list[numfree++] = so;
-	else 
-		Py_TYPE(so)->tp_free(so);
-	Py_TRASHCAN_SAFE_END(so)
+    for (entry = so->table; fill > 0; entry++) {
+        if (entry->key) {
+            --fill;
+            Py_DECREF(entry->key);
+        }
+    }
+    if (so->table != so->smalltable)
+        PyMem_DEL(so->table);
+    if (numfree < PySet_MAXFREELIST && PyAnySet_CheckExact(so))
+        free_list[numfree++] = so;
+    else
+        Py_TYPE(so)->tp_free(so);
+    Py_TRASHCAN_SAFE_END(so)
 }
 
 static PyObject *
 set_repr(PySetObject *so)
 {
-	PyObject *keys, *result=NULL;
-	Py_UNICODE *u;
-	int status = Py_ReprEnter((PyObject*)so);
-	PyObject *listrepr;
-	Py_ssize_t newsize;
+    PyObject *keys, *result=NULL;
+    Py_UNICODE *u;
+    int status = Py_ReprEnter((PyObject*)so);
+    PyObject *listrepr;
+    Py_ssize_t newsize;
 
-	if (status != 0) {
-		if (status < 0)
-			return NULL;
-		return PyUnicode_FromFormat("%s(...)", Py_TYPE(so)->tp_name);
-	}
+    if (status != 0) {
+        if (status < 0)
+            return NULL;
+        return PyUnicode_FromFormat("%s(...)", Py_TYPE(so)->tp_name);
+    }
 
-	/* shortcut for the empty set */
-	if (!so->used) {
-		Py_ReprLeave((PyObject*)so);
-		return PyUnicode_FromFormat("%s()", Py_TYPE(so)->tp_name);
-	}
+    /* shortcut for the empty set */
+    if (!so->used) {
+        Py_ReprLeave((PyObject*)so);
+        return PyUnicode_FromFormat("%s()", Py_TYPE(so)->tp_name);
+    }
 
-	keys = PySequence_List((PyObject *)so);
-	if (keys == NULL)
-		goto done;
+    keys = PySequence_List((PyObject *)so);
+    if (keys == NULL)
+        goto done;
 
-	listrepr = PyObject_Repr(keys);
-	Py_DECREF(keys);
-	if (listrepr == NULL)
-		goto done;
-	newsize = PyUnicode_GET_SIZE(listrepr);
-	result = PyUnicode_FromUnicode(NULL, newsize);
-	if (result) {
-		u = PyUnicode_AS_UNICODE(result);
-		*u++ = '{';
-		/* Omit the brackets from the listrepr */
-		Py_UNICODE_COPY(u, PyUnicode_AS_UNICODE(listrepr)+1,
-				   PyUnicode_GET_SIZE(listrepr)-2);
-		u += newsize-2;
-		*u++ = '}';
-	}
-	Py_DECREF(listrepr);
-	if (Py_TYPE(so) != &PySet_Type) {
-		PyObject *tmp = PyUnicode_FromFormat("%s(%U)",
-						     Py_TYPE(so)->tp_name,
-						     result);
-		Py_DECREF(result);
-		result = tmp;
-	}
+    listrepr = PyObject_Repr(keys);
+    Py_DECREF(keys);
+    if (listrepr == NULL)
+        goto done;
+    newsize = PyUnicode_GET_SIZE(listrepr);
+    result = PyUnicode_FromUnicode(NULL, newsize);
+    if (result) {
+        u = PyUnicode_AS_UNICODE(result);
+        *u++ = '{';
+        /* Omit the brackets from the listrepr */
+        Py_UNICODE_COPY(u, PyUnicode_AS_UNICODE(listrepr)+1,
+                           PyUnicode_GET_SIZE(listrepr)-2);
+        u += newsize-2;
+        *u++ = '}';
+    }
+    Py_DECREF(listrepr);
+    if (Py_TYPE(so) != &PySet_Type) {
+        PyObject *tmp = PyUnicode_FromFormat("%s(%U)",
+                                             Py_TYPE(so)->tp_name,
+                                             result);
+        Py_DECREF(result);
+        result = tmp;
+    }
 done:
-	Py_ReprLeave((PyObject*)so);
-	return result;
+    Py_ReprLeave((PyObject*)so);
+    return result;
 }
 
 static Py_ssize_t
 set_len(PyObject *so)
 {
-	return ((PySetObject *)so)->used;
+    return ((PySetObject *)so)->used;
 }
 
 static int
 set_merge(PySetObject *so, PyObject *otherset)
 {
-	PySetObject *other;
-	register Py_ssize_t i;
-	register setentry *entry;
+    PySetObject *other;
+    register Py_ssize_t i;
+    register setentry *entry;
 
-	assert (PyAnySet_Check(so));
-	assert (PyAnySet_Check(otherset));
+    assert (PyAnySet_Check(so));
+    assert (PyAnySet_Check(otherset));
 
-	other = (PySetObject*)otherset;
-	if (other == so || other->used == 0)
-		/* a.update(a) or a.update({}); nothing to do */
-		return 0;
-	/* Do one big resize at the start, rather than
-	 * incrementally resizing as we insert new keys.  Expect
-	 * that there will be no (or few) overlapping keys.
-	 */
-	if ((so->fill + other->used)*3 >= (so->mask+1)*2) {
-	   if (set_table_resize(so, (so->used + other->used)*2) != 0)
-		   return -1;
-	}
-	for (i = 0; i <= other->mask; i++) {
-		entry = &other->table[i];
-		if (entry->key != NULL && 
-		    entry->key != dummy) {
-			Py_INCREF(entry->key);
-			if (set_insert_key(so, entry->key, entry->hash) == -1) {
-				Py_DECREF(entry->key);
-				return -1;
-			}
-		}
-	}
-	return 0;
+    other = (PySetObject*)otherset;
+    if (other == so || other->used == 0)
+        /* a.update(a) or a.update({}); nothing to do */
+        return 0;
+    /* Do one big resize at the start, rather than
+     * incrementally resizing as we insert new keys.  Expect
+     * that there will be no (or few) overlapping keys.
+     */
+    if ((so->fill + other->used)*3 >= (so->mask+1)*2) {
+       if (set_table_resize(so, (so->used + other->used)*2) != 0)
+           return -1;
+    }
+    for (i = 0; i <= other->mask; i++) {
+        entry = &other->table[i];
+        if (entry->key != NULL &&
+            entry->key != dummy) {
+            Py_INCREF(entry->key);
+            if (set_insert_key(so, entry->key, entry->hash) == -1) {
+                Py_DECREF(entry->key);
+                return -1;
+            }
+        }
+    }
+    return 0;
 }
 
 static int
 set_contains_key(PySetObject *so, PyObject *key)
 {
-	long hash;
-	setentry *entry;
+    long hash;
+    setentry *entry;
 
-	if (!PyUnicode_CheckExact(key) ||
-	    (hash = ((PyUnicodeObject *) key)->hash) == -1) {
-		hash = PyObject_Hash(key);
-		if (hash == -1)
-			return -1;
-	}
-	entry = (so->lookup)(so, key, hash);
-	if (entry == NULL)
-		return -1;
-	key = entry->key;
-	return key != NULL && key != dummy;
+    if (!PyUnicode_CheckExact(key) ||
+        (hash = ((PyUnicodeObject *) key)->hash) == -1) {
+        hash = PyObject_Hash(key);
+        if (hash == -1)
+            return -1;
+    }
+    entry = (so->lookup)(so, key, hash);
+    if (entry == NULL)
+        return -1;
+    key = entry->key;
+    return key != NULL && key != dummy;
 }
 
 static int
 set_contains_entry(PySetObject *so, setentry *entry)
 {
-	PyObject *key;
-	setentry *lu_entry;
+    PyObject *key;
+    setentry *lu_entry;
 
-	lu_entry = (so->lookup)(so, entry->key, entry->hash);
-	if (lu_entry == NULL)
-		return -1;
-	key = lu_entry->key; 
-	return key != NULL && key != dummy;
+    lu_entry = (so->lookup)(so, entry->key, entry->hash);
+    if (lu_entry == NULL)
+        return -1;
+    key = lu_entry->key;
+    return key != NULL && key != dummy;
 }
 
 static PyObject *
 set_pop(PySetObject *so)
 {
-	register Py_ssize_t i = 0;
-	register setentry *entry;
-	PyObject *key;
+    register Py_ssize_t i = 0;
+    register setentry *entry;
+    PyObject *key;
 
-	assert (PyAnySet_Check(so));
-	if (so->used == 0) {
-		PyErr_SetString(PyExc_KeyError, "pop from an empty set");
-		return NULL;
-	}
+    assert (PyAnySet_Check(so));
+    if (so->used == 0) {
+        PyErr_SetString(PyExc_KeyError, "pop from an empty set");
+        return NULL;
+    }
 
-	/* Set entry to "the first" unused or dummy set entry.  We abuse
-	 * the hash field of slot 0 to hold a search finger:
-	 * If slot 0 has a value, use slot 0.
-	 * Else slot 0 is being used to hold a search finger,
-	 * and we use its hash value as the first index to look.
-	 */
-	entry = &so->table[0];
-	if (entry->key == NULL || entry->key == dummy) {
-		i = entry->hash;
-		/* The hash field may be a real hash value, or it may be a
-		 * legit search finger, or it may be a once-legit search
-		 * finger that's out of bounds now because it wrapped around
-		 * or the table shrunk -- simply make sure it's in bounds now.
-		 */
-		if (i > so->mask || i < 1)
-			i = 1;	/* skip slot 0 */
-		while ((entry = &so->table[i])->key == NULL || entry->key==dummy) {
-			i++;
-			if (i > so->mask)
-				i = 1;
-		}
-	}
-	key = entry->key;
-	Py_INCREF(dummy);
-	entry->key = dummy;
-	so->used--;
-	so->table[0].hash = i + 1;  /* next place to start */
-	return key;
+    /* Set entry to "the first" unused or dummy set entry.  We abuse
+     * the hash field of slot 0 to hold a search finger:
+     * If slot 0 has a value, use slot 0.
+     * Else slot 0 is being used to hold a search finger,
+     * and we use its hash value as the first index to look.
+     */
+    entry = &so->table[0];
+    if (entry->key == NULL || entry->key == dummy) {
+        i = entry->hash;
+        /* The hash field may be a real hash value, or it may be a
+         * legit search finger, or it may be a once-legit search
+         * finger that's out of bounds now because it wrapped around
+         * or the table shrunk -- simply make sure it's in bounds now.
+         */
+        if (i > so->mask || i < 1)
+            i = 1;              /* skip slot 0 */
+        while ((entry = &so->table[i])->key == NULL || entry->key==dummy) {
+            i++;
+            if (i > so->mask)
+                i = 1;
+        }
+    }
+    key = entry->key;
+    Py_INCREF(dummy);
+    entry->key = dummy;
+    so->used--;
+    so->table[0].hash = i + 1;  /* next place to start */
+    return key;
 }
 
 PyDoc_STRVAR(pop_doc, "Remove and return an arbitrary set element.\n\
@@ -750,289 +750,289 @@
 static int
 set_traverse(PySetObject *so, visitproc visit, void *arg)
 {
-	Py_ssize_t pos = 0;
-	setentry *entry;
+    Py_ssize_t pos = 0;
+    setentry *entry;
 
-	while (set_next(so, &pos, &entry))
-		Py_VISIT(entry->key);
-	return 0;
+    while (set_next(so, &pos, &entry))
+        Py_VISIT(entry->key);
+    return 0;
 }
 
 static long
 frozenset_hash(PyObject *self)
 {
-	PySetObject *so = (PySetObject *)self;
-	long h, hash = 1927868237L;
-	setentry *entry;
-	Py_ssize_t pos = 0;
+    PySetObject *so = (PySetObject *)self;
+    long h, hash = 1927868237L;
+    setentry *entry;
+    Py_ssize_t pos = 0;
 
-	if (so->hash != -1)
-		return so->hash;
+    if (so->hash != -1)
+        return so->hash;
 
-	hash *= PySet_GET_SIZE(self) + 1;
-	while (set_next(so, &pos, &entry)) {
-		/* Work to increase the bit dispersion for closely spaced hash
-		   values.  The is important because some use cases have many 
-		   combinations of a small number of elements with nearby 
-		   hashes so that many distinct combinations collapse to only 
-		   a handful of distinct hash values. */
-		h = entry->hash;
-		hash ^= (h ^ (h << 16) ^ 89869747L)  * 3644798167u;
-	}
-	hash = hash * 69069L + 907133923L;
-	if (hash == -1)
-		hash = 590923713L;
-	so->hash = hash;
-	return hash;
+    hash *= PySet_GET_SIZE(self) + 1;
+    while (set_next(so, &pos, &entry)) {
+        /* Work to increase the bit dispersion for closely spaced hash
+           values.  The is important because some use cases have many
+           combinations of a small number of elements with nearby
+           hashes so that many distinct combinations collapse to only
+           a handful of distinct hash values. */
+        h = entry->hash;
+        hash ^= (h ^ (h << 16) ^ 89869747L)  * 3644798167u;
+    }
+    hash = hash * 69069L + 907133923L;
+    if (hash == -1)
+        hash = 590923713L;
+    so->hash = hash;
+    return hash;
 }
 
 /***** Set iterator type ***********************************************/
 
 typedef struct {
-	PyObject_HEAD
-	PySetObject *si_set; /* Set to NULL when iterator is exhausted */
-	Py_ssize_t si_used;
-	Py_ssize_t si_pos;
-	Py_ssize_t len;
+    PyObject_HEAD
+    PySetObject *si_set; /* Set to NULL when iterator is exhausted */
+    Py_ssize_t si_used;
+    Py_ssize_t si_pos;
+    Py_ssize_t len;
 } setiterobject;
 
 static void
 setiter_dealloc(setiterobject *si)
 {
-	Py_XDECREF(si->si_set);
-	PyObject_GC_Del(si);
+    Py_XDECREF(si->si_set);
+    PyObject_GC_Del(si);
 }
 
 static int
 setiter_traverse(setiterobject *si, visitproc visit, void *arg)
 {
-	Py_VISIT(si->si_set);
-	return 0;
+    Py_VISIT(si->si_set);
+    return 0;
 }
 
 static PyObject *
 setiter_len(setiterobject *si)
 {
-	Py_ssize_t len = 0;
-	if (si->si_set != NULL && si->si_used == si->si_set->used)
-		len = si->len;
-	return PyLong_FromLong(len);
+    Py_ssize_t len = 0;
+    if (si->si_set != NULL && si->si_used == si->si_set->used)
+        len = si->len;
+    return PyLong_FromLong(len);
 }
 
 PyDoc_STRVAR(length_hint_doc, "Private method returning an estimate of len(list(it)).");
 
 static PyMethodDef setiter_methods[] = {
-	{"__length_hint__", (PyCFunction)setiter_len, METH_NOARGS, length_hint_doc},
- 	{NULL,		NULL}		/* sentinel */
+    {"__length_hint__", (PyCFunction)setiter_len, METH_NOARGS, length_hint_doc},
+    {NULL,              NULL}           /* sentinel */
 };
 
 static PyObject *setiter_iternext(setiterobject *si)
 {
-	PyObject *key;
-	register Py_ssize_t i, mask;
-	register setentry *entry;
-	PySetObject *so = si->si_set;
+    PyObject *key;
+    register Py_ssize_t i, mask;
+    register setentry *entry;
+    PySetObject *so = si->si_set;
 
-	if (so == NULL)
-		return NULL;
-	assert (PyAnySet_Check(so));
+    if (so == NULL)
+        return NULL;
+    assert (PyAnySet_Check(so));
 
-	if (si->si_used != so->used) {
-		PyErr_SetString(PyExc_RuntimeError,
-				"Set changed size during iteration");
-		si->si_used = -1; /* Make this state sticky */
-		return NULL;
-	}
+    if (si->si_used != so->used) {
+        PyErr_SetString(PyExc_RuntimeError,
+                        "Set changed size during iteration");
+        si->si_used = -1; /* Make this state sticky */
+        return NULL;
+    }
 
-	i = si->si_pos;
-	assert(i>=0);
-	entry = so->table;
-	mask = so->mask;
-	while (i <= mask && (entry[i].key == NULL || entry[i].key == dummy))
-		i++;
-	si->si_pos = i+1;
-	if (i > mask)
-		goto fail;
-	si->len--;
-	key = entry[i].key;
-	Py_INCREF(key);
-	return key;
+    i = si->si_pos;
+    assert(i>=0);
+    entry = so->table;
+    mask = so->mask;
+    while (i <= mask && (entry[i].key == NULL || entry[i].key == dummy))
+        i++;
+    si->si_pos = i+1;
+    if (i > mask)
+        goto fail;
+    si->len--;
+    key = entry[i].key;
+    Py_INCREF(key);
+    return key;
 
 fail:
-	Py_DECREF(so);
-	si->si_set = NULL;
-	return NULL;
+    Py_DECREF(so);
+    si->si_set = NULL;
+    return NULL;
 }
 
 PyTypeObject PySetIter_Type = {
-	PyVarObject_HEAD_INIT(&PyType_Type, 0)
-	"set_iterator",				/* tp_name */
-	sizeof(setiterobject),			/* tp_basicsize */
-	0,					/* tp_itemsize */
-	/* methods */
-	(destructor)setiter_dealloc, 		/* tp_dealloc */
-	0,					/* tp_print */
-	0,					/* tp_getattr */
-	0,					/* tp_setattr */
-	0,					/* tp_reserved */
-	0,					/* tp_repr */
-	0,					/* tp_as_number */
-	0,					/* tp_as_sequence */
-	0,					/* tp_as_mapping */
-	0,					/* tp_hash */
-	0,					/* tp_call */
-	0,					/* tp_str */
-	PyObject_GenericGetAttr,		/* tp_getattro */
-	0,					/* tp_setattro */
-	0,					/* tp_as_buffer */
-	Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC,/* tp_flags */
- 	0,					/* tp_doc */
- 	(traverseproc)setiter_traverse,		/* tp_traverse */
- 	0,					/* tp_clear */
-	0,					/* tp_richcompare */
-	0,					/* tp_weaklistoffset */
-	PyObject_SelfIter,			/* tp_iter */
-	(iternextfunc)setiter_iternext,		/* tp_iternext */
-	setiter_methods,			/* tp_methods */
-	0,
+    PyVarObject_HEAD_INIT(&PyType_Type, 0)
+    "set_iterator",                             /* tp_name */
+    sizeof(setiterobject),                      /* tp_basicsize */
+    0,                                          /* tp_itemsize */
+    /* methods */
+    (destructor)setiter_dealloc,                /* tp_dealloc */
+    0,                                          /* tp_print */
+    0,                                          /* tp_getattr */
+    0,                                          /* tp_setattr */
+    0,                                          /* tp_reserved */
+    0,                                          /* tp_repr */
+    0,                                          /* tp_as_number */
+    0,                                          /* tp_as_sequence */
+    0,                                          /* tp_as_mapping */
+    0,                                          /* tp_hash */
+    0,                                          /* tp_call */
+    0,                                          /* tp_str */
+    PyObject_GenericGetAttr,                    /* tp_getattro */
+    0,                                          /* tp_setattro */
+    0,                                          /* tp_as_buffer */
+    Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC,/* tp_flags */
+    0,                                          /* tp_doc */
+    (traverseproc)setiter_traverse,             /* tp_traverse */
+    0,                                          /* tp_clear */
+    0,                                          /* tp_richcompare */
+    0,                                          /* tp_weaklistoffset */
+    PyObject_SelfIter,                          /* tp_iter */
+    (iternextfunc)setiter_iternext,             /* tp_iternext */
+    setiter_methods,                            /* tp_methods */
+    0,
 };
 
 static PyObject *
 set_iter(PySetObject *so)
 {
-	setiterobject *si = PyObject_GC_New(setiterobject, &PySetIter_Type);
-	if (si == NULL)
-		return NULL;
-	Py_INCREF(so);
-	si->si_set = so;
-	si->si_used = so->used;
-	si->si_pos = 0;
-	si->len = so->used;
-	_PyObject_GC_TRACK(si);
-	return (PyObject *)si;
+    setiterobject *si = PyObject_GC_New(setiterobject, &PySetIter_Type);
+    if (si == NULL)
+        return NULL;
+    Py_INCREF(so);
+    si->si_set = so;
+    si->si_used = so->used;
+    si->si_pos = 0;
+    si->len = so->used;
+    _PyObject_GC_TRACK(si);
+    return (PyObject *)si;
 }
 
 static int
 set_update_internal(PySetObject *so, PyObject *other)
 {
-	PyObject *key, *it;
+    PyObject *key, *it;
 
-	if (PyAnySet_Check(other))
-		return set_merge(so, other);
+    if (PyAnySet_Check(other))
+        return set_merge(so, other);
 
-	if (PyDict_CheckExact(other)) {
-		PyObject *value;
-		Py_ssize_t pos = 0;
-		long hash;
-		Py_ssize_t dictsize = PyDict_Size(other);
+    if (PyDict_CheckExact(other)) {
+        PyObject *value;
+        Py_ssize_t pos = 0;
+        long hash;
+        Py_ssize_t dictsize = PyDict_Size(other);
 
-		/* Do one big resize at the start, rather than
-		* incrementally resizing as we insert new keys.  Expect
-		* that there will be no (or few) overlapping keys.
-		*/
-		if (dictsize == -1)
-			return -1;
-		if ((so->fill + dictsize)*3 >= (so->mask+1)*2) {
-			if (set_table_resize(so, (so->used + dictsize)*2) != 0)
-				return -1;
-		}
-		while (_PyDict_Next(other, &pos, &key, &value, &hash)) {
-			setentry an_entry;
+        /* Do one big resize at the start, rather than
+        * incrementally resizing as we insert new keys.  Expect
+        * that there will be no (or few) overlapping keys.
+        */
+        if (dictsize == -1)
+            return -1;
+        if ((so->fill + dictsize)*3 >= (so->mask+1)*2) {
+            if (set_table_resize(so, (so->used + dictsize)*2) != 0)
+                return -1;
+        }
+        while (_PyDict_Next(other, &pos, &key, &value, &hash)) {
+            setentry an_entry;
 
-			an_entry.hash = hash;
-			an_entry.key = key;
-			if (set_add_entry(so, &an_entry) == -1)
-				return -1;
-		}
-		return 0;
-	}
+            an_entry.hash = hash;
+            an_entry.key = key;
+            if (set_add_entry(so, &an_entry) == -1)
+                return -1;
+        }
+        return 0;
+    }
 
-	it = PyObject_GetIter(other);
-	if (it == NULL)
-		return -1;
+    it = PyObject_GetIter(other);
+    if (it == NULL)
+        return -1;
 
-	while ((key = PyIter_Next(it)) != NULL) {
-                if (set_add_key(so, key) == -1) {
-			Py_DECREF(it);
-			Py_DECREF(key);
-			return -1;
-                } 
-		Py_DECREF(key);
-	}
-	Py_DECREF(it);
-	if (PyErr_Occurred())
-		return -1;
-	return 0;
+    while ((key = PyIter_Next(it)) != NULL) {
+        if (set_add_key(so, key) == -1) {
+            Py_DECREF(it);
+            Py_DECREF(key);
+            return -1;
+        }
+        Py_DECREF(key);
+    }
+    Py_DECREF(it);
+    if (PyErr_Occurred())
+        return -1;
+    return 0;
 }
 
 static PyObject *
 set_update(PySetObject *so, PyObject *args)
 {
-	Py_ssize_t i;
+    Py_ssize_t i;
 
-	for (i=0 ; i<PyTuple_GET_SIZE(args) ; i++) {
-		PyObject *other = PyTuple_GET_ITEM(args, i);
-		if (set_update_internal(so, other) == -1)
-			return NULL;
-	}
-	Py_RETURN_NONE;
+    for (i=0 ; i<PyTuple_GET_SIZE(args) ; i++) {
+        PyObject *other = PyTuple_GET_ITEM(args, i);
+        if (set_update_internal(so, other) == -1)
+            return NULL;
+    }
+    Py_RETURN_NONE;
 }
 
-PyDoc_STRVAR(update_doc, 
+PyDoc_STRVAR(update_doc,
 "Update a set with the union of itself and others.");
 
 static PyObject *
 make_new_set(PyTypeObject *type, PyObject *iterable)
 {
-	register PySetObject *so = NULL;
+    register PySetObject *so = NULL;
 
-	if (dummy == NULL) { /* Auto-initialize dummy */
-		dummy = PyUnicode_FromString("<dummy key>");
-		if (dummy == NULL)
-			return NULL;
-	}
+    if (dummy == NULL) { /* Auto-initialize dummy */
+        dummy = PyUnicode_FromString("<dummy key>");
+        if (dummy == NULL)
+            return NULL;
+    }
 
-	/* create PySetObject structure */
-	if (numfree &&
-	    (type == &PySet_Type  ||  type == &PyFrozenSet_Type)) {
-		so = free_list[--numfree];
-		assert (so != NULL && PyAnySet_CheckExact(so));
-		Py_TYPE(so) = type;
-		_Py_NewReference((PyObject *)so);
-		EMPTY_TO_MINSIZE(so);
-		PyObject_GC_Track(so);
-	} else {
-		so = (PySetObject *)type->tp_alloc(type, 0);
-		if (so == NULL)
-			return NULL;
-		/* tp_alloc has already zeroed the structure */
-		assert(so->table == NULL && so->fill == 0 && so->used == 0);
-		INIT_NONZERO_SET_SLOTS(so);
-	}
+    /* create PySetObject structure */
+    if (numfree &&
+        (type == &PySet_Type  ||  type == &PyFrozenSet_Type)) {
+        so = free_list[--numfree];
+        assert (so != NULL && PyAnySet_CheckExact(so));
+        Py_TYPE(so) = type;
+        _Py_NewReference((PyObject *)so);
+        EMPTY_TO_MINSIZE(so);
+        PyObject_GC_Track(so);
+    } else {
+        so = (PySetObject *)type->tp_alloc(type, 0);
+        if (so == NULL)
+            return NULL;
+        /* tp_alloc has already zeroed the structure */
+        assert(so->table == NULL && so->fill == 0 && so->used == 0);
+        INIT_NONZERO_SET_SLOTS(so);
+    }
 
-	so->lookup = set_lookkey_unicode;
-	so->weakreflist = NULL;
+    so->lookup = set_lookkey_unicode;
+    so->weakreflist = NULL;
 
-	if (iterable != NULL) {
-		if (set_update_internal(so, iterable) == -1) {
-			Py_DECREF(so);
-			return NULL;
-		}
-	}
+    if (iterable != NULL) {
+        if (set_update_internal(so, iterable) == -1) {
+            Py_DECREF(so);
+            return NULL;
+        }
+    }
 
-	return (PyObject *)so;
+    return (PyObject *)so;
 }
 
 static PyObject *
 make_new_set_basetype(PyTypeObject *type, PyObject *iterable)
 {
-	if (type != &PySet_Type && type != &PyFrozenSet_Type) {
-		if (PyType_IsSubtype(type, &PySet_Type))
-			type = &PySet_Type;
-		else
-			type = &PyFrozenSet_Type;
-	}
-	return make_new_set(type, iterable);
+    if (type != &PySet_Type && type != &PyFrozenSet_Type) {
+        if (PyType_IsSubtype(type, &PySet_Type))
+            type = &PySet_Type;
+        else
+            type = &PyFrozenSet_Type;
+    }
+    return make_new_set(type, iterable);
 }
 
 /* The empty frozenset is a singleton */
@@ -1041,56 +1041,56 @@
 static PyObject *
 frozenset_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
 {
-	PyObject *iterable = NULL, *result;
+    PyObject *iterable = NULL, *result;
 
-	if (type == &PyFrozenSet_Type && !_PyArg_NoKeywords("frozenset()", kwds))
-		return NULL;
+    if (type == &PyFrozenSet_Type && !_PyArg_NoKeywords("frozenset()", kwds))
+        return NULL;
 
-	if (!PyArg_UnpackTuple(args, type->tp_name, 0, 1, &iterable))
-		return NULL;
+    if (!PyArg_UnpackTuple(args, type->tp_name, 0, 1, &iterable))
+        return NULL;
 
-	if (type != &PyFrozenSet_Type)
-		return make_new_set(type, iterable);
+    if (type != &PyFrozenSet_Type)
+        return make_new_set(type, iterable);
 
-	if (iterable != NULL) {
-		/* frozenset(f) is idempotent */
-		if (PyFrozenSet_CheckExact(iterable)) {
-			Py_INCREF(iterable);
-			return iterable;
-		}
-		result = make_new_set(type, iterable);
-		if (result == NULL || PySet_GET_SIZE(result))
-			return result;
-		Py_DECREF(result);
-	}
-	/* The empty frozenset is a singleton */
-	if (emptyfrozenset == NULL)
-		emptyfrozenset = make_new_set(type, NULL);
-	Py_XINCREF(emptyfrozenset);
-	return emptyfrozenset;
+    if (iterable != NULL) {
+        /* frozenset(f) is idempotent */
+        if (PyFrozenSet_CheckExact(iterable)) {
+            Py_INCREF(iterable);
+            return iterable;
+        }
+        result = make_new_set(type, iterable);
+        if (result == NULL || PySet_GET_SIZE(result))
+            return result;
+        Py_DECREF(result);
+    }
+    /* The empty frozenset is a singleton */
+    if (emptyfrozenset == NULL)
+        emptyfrozenset = make_new_set(type, NULL);
+    Py_XINCREF(emptyfrozenset);
+    return emptyfrozenset;
 }
 
 void
 PySet_Fini(void)
 {
-	PySetObject *so;
+    PySetObject *so;
 
-	while (numfree) {
-		numfree--;
-		so = free_list[numfree];
-		PyObject_GC_Del(so);
-	}
-	Py_CLEAR(dummy);
-	Py_CLEAR(emptyfrozenset);
+    while (numfree) {
+        numfree--;
+        so = free_list[numfree];
+        PyObject_GC_Del(so);
+    }
+    Py_CLEAR(dummy);
+    Py_CLEAR(emptyfrozenset);
 }
 
 static PyObject *
 set_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
 {
-	if (type == &PySet_Type && !_PyArg_NoKeywords("set()", kwds))
-		return NULL;
-	
-	return make_new_set(type, NULL);
+    if (type == &PySet_Type && !_PyArg_NoKeywords("set()", kwds))
+        return NULL;
+
+    return make_new_set(type, NULL);
 }
 
 /* set_swap_bodies() switches the contents of any two sets by moving their
@@ -1100,64 +1100,64 @@
      t=set(a); a.clear(); a.update(b); b.clear(); b.update(t); del t
 
    The function always succeeds and it leaves both objects in a stable state.
-   Useful for creating temporary frozensets from sets for membership testing 
+   Useful for creating temporary frozensets from sets for membership testing
    in __contains__(), discard(), and remove().  Also useful for operations
-   that update in-place (by allowing an intermediate result to be swapped 
+   that update in-place (by allowing an intermediate result to be swapped
    into one of the original inputs).
 */
 
 static void
 set_swap_bodies(PySetObject *a, PySetObject *b)
 {
-	Py_ssize_t t;
-	setentry *u;
-	setentry *(*f)(PySetObject *so, PyObject *key, long hash);
-	setentry tab[PySet_MINSIZE];
-	long h;
+    Py_ssize_t t;
+    setentry *u;
+    setentry *(*f)(PySetObject *so, PyObject *key, long hash);
+    setentry tab[PySet_MINSIZE];
+    long h;
 
-	t = a->fill;     a->fill   = b->fill;        b->fill  = t;
-	t = a->used;     a->used   = b->used;        b->used  = t;
-	t = a->mask;     a->mask   = b->mask;        b->mask  = t;
+    t = a->fill;     a->fill   = b->fill;        b->fill  = t;
+    t = a->used;     a->used   = b->used;        b->used  = t;
+    t = a->mask;     a->mask   = b->mask;        b->mask  = t;
 
-	u = a->table;
-	if (a->table == a->smalltable)
-		u = b->smalltable;
-	a->table  = b->table;
-	if (b->table == b->smalltable)
-		a->table = a->smalltable;
-	b->table = u;
+    u = a->table;
+    if (a->table == a->smalltable)
+        u = b->smalltable;
+    a->table  = b->table;
+    if (b->table == b->smalltable)
+        a->table = a->smalltable;
+    b->table = u;
 
-	f = a->lookup;   a->lookup = b->lookup;      b->lookup = f;
+    f = a->lookup;   a->lookup = b->lookup;      b->lookup = f;
 
-	if (a->table == a->smalltable || b->table == b->smalltable) {
-		memcpy(tab, a->smalltable, sizeof(tab));
-		memcpy(a->smalltable, b->smalltable, sizeof(tab));
-		memcpy(b->smalltable, tab, sizeof(tab));
-	}
+    if (a->table == a->smalltable || b->table == b->smalltable) {
+        memcpy(tab, a->smalltable, sizeof(tab));
+        memcpy(a->smalltable, b->smalltable, sizeof(tab));
+        memcpy(b->smalltable, tab, sizeof(tab));
+    }
 
-	if (PyType_IsSubtype(Py_TYPE(a), &PyFrozenSet_Type)  &&
-	    PyType_IsSubtype(Py_TYPE(b), &PyFrozenSet_Type)) {
-		h = a->hash;     a->hash = b->hash;  b->hash = h;
-	} else {
-		a->hash = -1;
-		b->hash = -1;
-	}
+    if (PyType_IsSubtype(Py_TYPE(a), &PyFrozenSet_Type)  &&
+        PyType_IsSubtype(Py_TYPE(b), &PyFrozenSet_Type)) {
+        h = a->hash;     a->hash = b->hash;  b->hash = h;
+    } else {
+        a->hash = -1;
+        b->hash = -1;
+    }
 }
 
 static PyObject *
 set_copy(PySetObject *so)
 {
-	return make_new_set_basetype(Py_TYPE(so), (PyObject *)so);
+    return make_new_set_basetype(Py_TYPE(so), (PyObject *)so);
 }
 
 static PyObject *
 frozenset_copy(PySetObject *so)
 {
-	if (PyFrozenSet_CheckExact(so)) {
-		Py_INCREF(so);
-		return (PyObject *)so;
-	}
-	return set_copy(so);
+    if (PyFrozenSet_CheckExact(so)) {
+        Py_INCREF(so);
+        return (PyObject *)so;
+    }
+    return set_copy(so);
 }
 
 PyDoc_STRVAR(copy_doc, "Return a shallow copy of a set.");
@@ -1165,8 +1165,8 @@
 static PyObject *
 set_clear(PySetObject *so)
 {
-	set_clear_internal(so);
-	Py_RETURN_NONE;
+    set_clear_internal(so);
+    Py_RETURN_NONE;
 }
 
 PyDoc_STRVAR(clear_doc, "Remove all elements from this set.");
@@ -1174,24 +1174,24 @@
 static PyObject *
 set_union(PySetObject *so, PyObject *args)
 {
-	PySetObject *result;
-	PyObject *other;
-	Py_ssize_t i;
+    PySetObject *result;
+    PyObject *other;
+    Py_ssize_t i;
 
-	result = (PySetObject *)set_copy(so);
-	if (result == NULL)
-		return NULL;
+    result = (PySetObject *)set_copy(so);
+    if (result == NULL)
+        return NULL;
 
-	for (i=0 ; i<PyTuple_GET_SIZE(args) ; i++) {
-		other = PyTuple_GET_ITEM(args, i);
-		if ((PyObject *)so == other)
-			continue;
-		if (set_update_internal(result, other) == -1) {
-			Py_DECREF(result);
-			return NULL;
-		}
-	}
-	return (PyObject *)result;
+    for (i=0 ; i<PyTuple_GET_SIZE(args) ; i++) {
+        other = PyTuple_GET_ITEM(args, i);
+        if ((PyObject *)so == other)
+            continue;
+        if (set_update_internal(result, other) == -1) {
+            Py_DECREF(result);
+            return NULL;
+        }
+    }
+    return (PyObject *)result;
 }
 
 PyDoc_STRVAR(union_doc,
@@ -1202,142 +1202,142 @@
 static PyObject *
 set_or(PySetObject *so, PyObject *other)
 {
-	PySetObject *result;
+    PySetObject *result;
 
-	if (!PyAnySet_Check(so) || !PyAnySet_Check(other)) {
-		Py_INCREF(Py_NotImplemented);
-		return Py_NotImplemented;
-	}
+    if (!PyAnySet_Check(so) || !PyAnySet_Check(other)) {
+        Py_INCREF(Py_NotImplemented);
+        return Py_NotImplemented;
+    }
 
-	result = (PySetObject *)set_copy(so);
-	if (result == NULL)
-		return NULL;
-	if ((PyObject *)so == other)
-		return (PyObject *)result;
-	if (set_update_internal(result, other) == -1) {
-		Py_DECREF(result);
-		return NULL;
-	}
-	return (PyObject *)result;
+    result = (PySetObject *)set_copy(so);
+    if (result == NULL)
+        return NULL;
+    if ((PyObject *)so == other)
+        return (PyObject *)result;
+    if (set_update_internal(result, other) == -1) {
+        Py_DECREF(result);
+        return NULL;
+    }
+    return (PyObject *)result;
 }
 
 static PyObject *
 set_ior(PySetObject *so, PyObject *other)
 {
-	if (!PyAnySet_Check(other)) {
-		Py_INCREF(Py_NotImplemented);
-		return Py_NotImplemented;
-	}
-	if (set_update_internal(so, other) == -1)
-		return NULL;
-	Py_INCREF(so);
-	return (PyObject *)so;
+    if (!PyAnySet_Check(other)) {
+        Py_INCREF(Py_NotImplemented);
+        return Py_NotImplemented;
+    }
+    if (set_update_internal(so, other) == -1)
+        return NULL;
+    Py_INCREF(so);
+    return (PyObject *)so;
 }
 
 static PyObject *
 set_intersection(PySetObject *so, PyObject *other)
 {
-	PySetObject *result;
-	PyObject *key, *it, *tmp;
+    PySetObject *result;
+    PyObject *key, *it, *tmp;
 
-	if ((PyObject *)so == other)
-		return set_copy(so);
+    if ((PyObject *)so == other)
+        return set_copy(so);
 
-	result = (PySetObject *)make_new_set_basetype(Py_TYPE(so), NULL);
-	if (result == NULL)
-		return NULL;
+    result = (PySetObject *)make_new_set_basetype(Py_TYPE(so), NULL);
+    if (result == NULL)
+        return NULL;
 
-	if (PyAnySet_Check(other)) {		
-		Py_ssize_t pos = 0;
-		setentry *entry;
+    if (PyAnySet_Check(other)) {
+        Py_ssize_t pos = 0;
+        setentry *entry;
 
-		if (PySet_GET_SIZE(other) > PySet_GET_SIZE(so)) {
-			tmp = (PyObject *)so;
-			so = (PySetObject *)other;
-			other = tmp;
-		}
+        if (PySet_GET_SIZE(other) > PySet_GET_SIZE(so)) {
+            tmp = (PyObject *)so;
+            so = (PySetObject *)other;
+            other = tmp;
+        }
 
-		while (set_next((PySetObject *)other, &pos, &entry)) {
-			int rv = set_contains_entry(so, entry);
-			if (rv == -1) {
-				Py_DECREF(result);
-				return NULL;
-			}
-			if (rv) {
-				if (set_add_entry(result, entry) == -1) {
-					Py_DECREF(result);
-					return NULL;
-				}
-			}
-		}
-		return (PyObject *)result;
-	}
+        while (set_next((PySetObject *)other, &pos, &entry)) {
+            int rv = set_contains_entry(so, entry);
+            if (rv == -1) {
+                Py_DECREF(result);
+                return NULL;
+            }
+            if (rv) {
+                if (set_add_entry(result, entry) == -1) {
+                    Py_DECREF(result);
+                    return NULL;
+                }
+            }
+        }
+        return (PyObject *)result;
+    }
 
-	it = PyObject_GetIter(other);
-	if (it == NULL) {
-		Py_DECREF(result);
-		return NULL;
-	}
+    it = PyObject_GetIter(other);
+    if (it == NULL) {
+        Py_DECREF(result);
+        return NULL;
+    }
 
-	while ((key = PyIter_Next(it)) != NULL) {
-		int rv;
-		setentry entry;
-		long hash = PyObject_Hash(key);
+    while ((key = PyIter_Next(it)) != NULL) {
+        int rv;
+        setentry entry;
+        long hash = PyObject_Hash(key);
 
-		if (hash == -1) {
-			Py_DECREF(it);
-			Py_DECREF(result);
-			Py_DECREF(key);
-			return NULL;
-		}
-		entry.hash = hash;
-		entry.key = key;
-		rv = set_contains_entry(so, &entry);
-		if (rv == -1) {
-			Py_DECREF(it);
-			Py_DECREF(result);
-			Py_DECREF(key);
-			return NULL;
-		}
-		if (rv) {
-			if (set_add_entry(result, &entry) == -1) {
-				Py_DECREF(it);
-				Py_DECREF(result);
-				Py_DECREF(key);
-				return NULL;
-			}
-		}
-		Py_DECREF(key);
-	}
-	Py_DECREF(it);
-	if (PyErr_Occurred()) {
-		Py_DECREF(result);
-		return NULL;
-	}
-	return (PyObject *)result;
+        if (hash == -1) {
+            Py_DECREF(it);
+            Py_DECREF(result);
+            Py_DECREF(key);
+            return NULL;
+        }
+        entry.hash = hash;
+        entry.key = key;
+        rv = set_contains_entry(so, &entry);
+        if (rv == -1) {
+            Py_DECREF(it);
+            Py_DECREF(result);
+            Py_DECREF(key);
+            return NULL;
+        }
+        if (rv) {
+            if (set_add_entry(result, &entry) == -1) {
+                Py_DECREF(it);
+                Py_DECREF(result);
+                Py_DECREF(key);
+                return NULL;
+            }
+        }
+        Py_DECREF(key);
+    }
+    Py_DECREF(it);
+    if (PyErr_Occurred()) {
+        Py_DECREF(result);
+        return NULL;
+    }
+    return (PyObject *)result;
 }
 
 static PyObject *
 set_intersection_multi(PySetObject *so, PyObject *args)
 {
-	Py_ssize_t i;
-	PyObject *result = (PyObject *)so;
+    Py_ssize_t i;
+    PyObject *result = (PyObject *)so;
 
-	if (PyTuple_GET_SIZE(args) == 0)
-		return set_copy(so);
+    if (PyTuple_GET_SIZE(args) == 0)
+        return set_copy(so);
 
-	Py_INCREF(so);
-	for (i=0 ; i<PyTuple_GET_SIZE(args) ; i++) {
-		PyObject *other = PyTuple_GET_ITEM(args, i);
-		PyObject *newresult = set_intersection((PySetObject *)result, other);
-		if (newresult == NULL) {
-			Py_DECREF(result);
-			return NULL;
-		}
-		Py_DECREF(result);
-		result = newresult;
-	}
-	return result;
+    Py_INCREF(so);
+    for (i=0 ; i<PyTuple_GET_SIZE(args) ; i++) {
+        PyObject *other = PyTuple_GET_ITEM(args, i);
+        PyObject *newresult = set_intersection((PySetObject *)result, other);
+        if (newresult == NULL) {
+            Py_DECREF(result);
+            return NULL;
+        }
+        Py_DECREF(result);
+        result = newresult;
+    }
+    return result;
 }
 
 PyDoc_STRVAR(intersection_doc,
@@ -1348,27 +1348,27 @@
 static PyObject *
 set_intersection_update(PySetObject *so, PyObject *other)
 {
-	PyObject *tmp;
+    PyObject *tmp;
 
-	tmp = set_intersection(so, other);
-	if (tmp == NULL)
-		return NULL;
-	set_swap_bodies(so, (PySetObject *)tmp);
-	Py_DECREF(tmp);
-	Py_RETURN_NONE;
+    tmp = set_intersection(so, other);
+    if (tmp == NULL)
+        return NULL;
+    set_swap_bodies(so, (PySetObject *)tmp);
+    Py_DECREF(tmp);
+    Py_RETURN_NONE;
 }
 
 static PyObject *
 set_intersection_update_multi(PySetObject *so, PyObject *args)
 {
-	PyObject *tmp;
+    PyObject *tmp;
 
-	tmp = set_intersection_multi(so, args);
-	if (tmp == NULL)
-		return NULL;
-	set_swap_bodies(so, (PySetObject *)tmp);
-	Py_DECREF(tmp);
-	Py_RETURN_NONE;
+    tmp = set_intersection_multi(so, args);
+    if (tmp == NULL)
+        return NULL;
+    set_swap_bodies(so, (PySetObject *)tmp);
+    Py_DECREF(tmp);
+    Py_RETURN_NONE;
 }
 
 PyDoc_STRVAR(intersection_update_doc,
@@ -1377,92 +1377,92 @@
 static PyObject *
 set_and(PySetObject *so, PyObject *other)
 {
-	if (!PyAnySet_Check(so) || !PyAnySet_Check(other)) {
-		Py_INCREF(Py_NotImplemented);
-		return Py_NotImplemented;
-	}
-	return set_intersection(so, other);
+    if (!PyAnySet_Check(so) || !PyAnySet_Check(other)) {
+        Py_INCREF(Py_NotImplemented);
+        return Py_NotImplemented;
+    }
+    return set_intersection(so, other);
 }
 
 static PyObject *
 set_iand(PySetObject *so, PyObject *other)
 {
-	PyObject *result;
+    PyObject *result;
 
-	if (!PyAnySet_Check(other)) {
-		Py_INCREF(Py_NotImplemented);
-		return Py_NotImplemented;
-	}
-	result = set_intersection_update(so, other);
-	if (result == NULL)
-		return NULL;
-	Py_DECREF(result);
-	Py_INCREF(so);
-	return (PyObject *)so;
+    if (!PyAnySet_Check(other)) {
+        Py_INCREF(Py_NotImplemented);
+        return Py_NotImplemented;
+    }
+    result = set_intersection_update(so, other);
+    if (result == NULL)
+        return NULL;
+    Py_DECREF(result);
+    Py_INCREF(so);
+    return (PyObject *)so;
 }
 
 static PyObject *
 set_isdisjoint(PySetObject *so, PyObject *other)
 {
-	PyObject *key, *it, *tmp;
+    PyObject *key, *it, *tmp;
 
-	if ((PyObject *)so == other) {
-		if (PySet_GET_SIZE(so) == 0)
-			Py_RETURN_TRUE;
-		else
-			Py_RETURN_FALSE;
-	}
+    if ((PyObject *)so == other) {
+        if (PySet_GET_SIZE(so) == 0)
+            Py_RETURN_TRUE;
+        else
+            Py_RETURN_FALSE;
+    }
 
-	if (PyAnySet_CheckExact(other)) {		
-		Py_ssize_t pos = 0;
-		setentry *entry;
+    if (PyAnySet_CheckExact(other)) {
+        Py_ssize_t pos = 0;
+        setentry *entry;
 
-		if (PySet_GET_SIZE(other) > PySet_GET_SIZE(so)) {
-			tmp = (PyObject *)so;
-			so = (PySetObject *)other;
-			other = tmp;
-		}
-		while (set_next((PySetObject *)other, &pos, &entry)) {
-			int rv = set_contains_entry(so, entry);
-			if (rv == -1)
-				return NULL;
-			if (rv)
-				Py_RETURN_FALSE;
-		}
-		Py_RETURN_TRUE;
-	}
+        if (PySet_GET_SIZE(other) > PySet_GET_SIZE(so)) {
+            tmp = (PyObject *)so;
+            so = (PySetObject *)other;
+            other = tmp;
+        }
+        while (set_next((PySetObject *)other, &pos, &entry)) {
+            int rv = set_contains_entry(so, entry);
+            if (rv == -1)
+                return NULL;
+            if (rv)
+                Py_RETURN_FALSE;
+        }
+        Py_RETURN_TRUE;
+    }
 
-	it = PyObject_GetIter(other);
-	if (it == NULL)
-		return NULL;
+    it = PyObject_GetIter(other);
+    if (it == NULL)
+        return NULL;
 
-	while ((key = PyIter_Next(it)) != NULL) {
-		int rv;
-		setentry entry;
-		long hash = PyObject_Hash(key);;
+    while ((key = PyIter_Next(it)) != NULL) {
+        int rv;
+        setentry entry;
+        long hash = PyObject_Hash(key);;
 
-		if (hash == -1) {
-			Py_DECREF(key);
-			Py_DECREF(it);
-			return NULL;
-		}
-		entry.hash = hash;
-		entry.key = key;
-		rv = set_contains_entry(so, &entry);
-		Py_DECREF(key);
-		if (rv == -1) {
-			Py_DECREF(it);
-			return NULL;
-		}
-		if (rv) {
-			Py_DECREF(it);
-			Py_RETURN_FALSE;
-		}
-	}
-	Py_DECREF(it);
-	if (PyErr_Occurred())
-		return NULL;
-	Py_RETURN_TRUE;
+        if (hash == -1) {
+            Py_DECREF(key);
+            Py_DECREF(it);
+            return NULL;
+        }
+        entry.hash = hash;
+        entry.key = key;
+        rv = set_contains_entry(so, &entry);
+        Py_DECREF(key);
+        if (rv == -1) {
+            Py_DECREF(it);
+            return NULL;
+        }
+        if (rv) {
+            Py_DECREF(it);
+            Py_RETURN_FALSE;
+        }
+    }
+    Py_DECREF(it);
+    if (PyErr_Occurred())
+        return NULL;
+    Py_RETURN_TRUE;
 }
 
 PyDoc_STRVAR(isdisjoint_doc,
@@ -1471,51 +1471,51 @@
 static int
 set_difference_update_internal(PySetObject *so, PyObject *other)
 {
-	if ((PyObject *)so == other)
-		return set_clear_internal(so);
-	
-	if (PyAnySet_Check(other)) {
-		setentry *entry;
-		Py_ssize_t pos = 0;
+    if ((PyObject *)so == other)
+        return set_clear_internal(so);
 
-		while (set_next((PySetObject *)other, &pos, &entry))
-			if (set_discard_entry(so, entry) == -1)
-				return -1;
-	} else {
-		PyObject *key, *it;
-		it = PyObject_GetIter(other);
-		if (it == NULL)
-			return -1;
+    if (PyAnySet_Check(other)) {
+        setentry *entry;
+        Py_ssize_t pos = 0;
 
-		while ((key = PyIter_Next(it)) != NULL) {
-			if (set_discard_key(so, key) == -1) {
-				Py_DECREF(it);
-				Py_DECREF(key);
-				return -1;
-			}
-			Py_DECREF(key);
-		}
-		Py_DECREF(it);
-		if (PyErr_Occurred())
-			return -1;
-	}
-	/* If more than 1/5 are dummies, then resize them away. */
-	if ((so->fill - so->used) * 5 < so->mask)
-		return 0;
-	return set_table_resize(so, so->used>50000 ? so->used*2 : so->used*4);
+        while (set_next((PySetObject *)other, &pos, &entry))
+            if (set_discard_entry(so, entry) == -1)
+                return -1;
+    } else {
+        PyObject *key, *it;
+        it = PyObject_GetIter(other);
+        if (it == NULL)
+            return -1;
+
+        while ((key = PyIter_Next(it)) != NULL) {
+            if (set_discard_key(so, key) == -1) {
+                Py_DECREF(it);
+                Py_DECREF(key);
+                return -1;
+            }
+            Py_DECREF(key);
+        }
+        Py_DECREF(it);
+        if (PyErr_Occurred())
+            return -1;
+    }
+    /* If more than 1/5 are dummies, then resize them away. */
+    if ((so->fill - so->used) * 5 < so->mask)
+        return 0;
+    return set_table_resize(so, so->used>50000 ? so->used*2 : so->used*4);
 }
 
 static PyObject *
 set_difference_update(PySetObject *so, PyObject *args)
 {
-	Py_ssize_t i;
+    Py_ssize_t i;
 
-	for (i=0 ; i<PyTuple_GET_SIZE(args) ; i++) {
-		PyObject *other = PyTuple_GET_ITEM(args, i);
-		if (set_difference_update_internal(so, other) == -1)
-			return NULL;
-	}
-	Py_RETURN_NONE;
+    for (i=0 ; i<PyTuple_GET_SIZE(args) ; i++) {
+        PyObject *other = PyTuple_GET_ITEM(args, i);
+        if (set_difference_update_internal(so, other) == -1)
+            return NULL;
+    }
+    Py_RETURN_NONE;
 }
 
 PyDoc_STRVAR(difference_update_doc,
@@ -1524,77 +1524,77 @@
 static PyObject *
 set_difference(PySetObject *so, PyObject *other)
 {
-	PyObject *result;
-	setentry *entry;
-	Py_ssize_t pos = 0;
+    PyObject *result;
+    setentry *entry;
+    Py_ssize_t pos = 0;
 
-	if (!PyAnySet_Check(other)  && !PyDict_CheckExact(other)) {
-		result = set_copy(so);
-		if (result == NULL)
-			return NULL;
-		if (set_difference_update_internal((PySetObject *)result, other) != -1)
-			return result;
-		Py_DECREF(result);
-		return NULL;
-	}
-	
-	result = make_new_set_basetype(Py_TYPE(so), NULL);
-	if (result == NULL)
-		return NULL;
+    if (!PyAnySet_Check(other)  && !PyDict_CheckExact(other)) {
+        result = set_copy(so);
+        if (result == NULL)
+            return NULL;
+        if (set_difference_update_internal((PySetObject *)result, other) != -1)
+            return result;
+        Py_DECREF(result);
+        return NULL;
+    }
 
-	if (PyDict_CheckExact(other)) {
-		while (set_next(so, &pos, &entry)) {
-			setentry entrycopy;
-			entrycopy.hash = entry->hash;
-			entrycopy.key = entry->key;
-			if (!_PyDict_Contains(other, entry->key, entry->hash)) {
-				if (set_add_entry((PySetObject *)result, &entrycopy) == -1) {
-					Py_DECREF(result);
-					return NULL;
-				}
-			}
-		}
-		return result;
-	}
+    result = make_new_set_basetype(Py_TYPE(so), NULL);
+    if (result == NULL)
+        return NULL;
 
-	while (set_next(so, &pos, &entry)) {
-		int rv = set_contains_entry((PySetObject *)other, entry);
-		if (rv == -1) {
-			Py_DECREF(result);
-			return NULL;
-		}
-		if (!rv) {
-			if (set_add_entry((PySetObject *)result, entry) == -1) {
-				Py_DECREF(result);
-				return NULL;
-			}
-		}
-	}
-	return result;
+    if (PyDict_CheckExact(other)) {
+        while (set_next(so, &pos, &entry)) {
+            setentry entrycopy;
+            entrycopy.hash = entry->hash;
+            entrycopy.key = entry->key;
+            if (!_PyDict_Contains(other, entry->key, entry->hash)) {
+                if (set_add_entry((PySetObject *)result, &entrycopy) == -1) {
+                    Py_DECREF(result);
+                    return NULL;
+                }
+            }
+        }
+        return result;
+    }
+
+    while (set_next(so, &pos, &entry)) {
+        int rv = set_contains_entry((PySetObject *)other, entry);
+        if (rv == -1) {
+            Py_DECREF(result);
+            return NULL;
+        }
+        if (!rv) {
+            if (set_add_entry((PySetObject *)result, entry) == -1) {
+                Py_DECREF(result);
+                return NULL;
+            }
+        }
+    }
+    return result;
 }
 
 static PyObject *
 set_difference_multi(PySetObject *so, PyObject *args)
 {
-	Py_ssize_t i;
-	PyObject *result, *other;
+    Py_ssize_t i;
+    PyObject *result, *other;
 
-	if (PyTuple_GET_SIZE(args) == 0)
-		return set_copy(so);
+    if (PyTuple_GET_SIZE(args) == 0)
+        return set_copy(so);
 
-	other = PyTuple_GET_ITEM(args, 0);
-	result = set_difference(so, other);
-	if (result == NULL)
-		return NULL;
+    other = PyTuple_GET_ITEM(args, 0);
+    result = set_difference(so, other);
+    if (result == NULL)
+        return NULL;
 
-	for (i=1 ; i<PyTuple_GET_SIZE(args) ; i++) {
-		other = PyTuple_GET_ITEM(args, i);
-		if (set_difference_update_internal((PySetObject *)result, other) == -1) {
-			Py_DECREF(result);
-			return NULL;
-		}
-	}
-	return result;
+    for (i=1 ; i<PyTuple_GET_SIZE(args) ; i++) {
+        other = PyTuple_GET_ITEM(args, i);
+        if (set_difference_update_internal((PySetObject *)result, other) == -1) {
+            Py_DECREF(result);
+            return NULL;
+        }
+    }
+    return result;
 }
 
 PyDoc_STRVAR(difference_doc,
@@ -1604,81 +1604,81 @@
 static PyObject *
 set_sub(PySetObject *so, PyObject *other)
 {
-	if (!PyAnySet_Check(so) || !PyAnySet_Check(other)) {
-		Py_INCREF(Py_NotImplemented);
-		return Py_NotImplemented;
-	}
-	return set_difference(so, other);
+    if (!PyAnySet_Check(so) || !PyAnySet_Check(other)) {
+        Py_INCREF(Py_NotImplemented);
+        return Py_NotImplemented;
+    }
+    return set_difference(so, other);
 }
 
 static PyObject *
 set_isub(PySetObject *so, PyObject *other)
 {
-	if (!PyAnySet_Check(other)) {
-		Py_INCREF(Py_NotImplemented);
-		return Py_NotImplemented;
-	}
-	if (set_difference_update_internal(so, other) == -1)
-		return NULL;
-	Py_INCREF(so);
-	return (PyObject *)so;
+    if (!PyAnySet_Check(other)) {
+        Py_INCREF(Py_NotImplemented);
+        return Py_NotImplemented;
+    }
+    if (set_difference_update_internal(so, other) == -1)
+        return NULL;
+    Py_INCREF(so);
+    return (PyObject *)so;
 }
 
 static PyObject *
 set_symmetric_difference_update(PySetObject *so, PyObject *other)
 {
-	PySetObject *otherset;
-	PyObject *key;
-	Py_ssize_t pos = 0;
-	setentry *entry;
+    PySetObject *otherset;
+    PyObject *key;
+    Py_ssize_t pos = 0;
+    setentry *entry;
 
-	if ((PyObject *)so == other)
-		return set_clear(so);
+    if ((PyObject *)so == other)
+        return set_clear(so);
 
-	if (PyDict_CheckExact(other)) {
-		PyObject *value;
-		int rv;
-		long hash;
-		while (_PyDict_Next(other, &pos, &key, &value, &hash)) {
-			setentry an_entry;
+    if (PyDict_CheckExact(other)) {
+        PyObject *value;
+        int rv;
+        long hash;
+        while (_PyDict_Next(other, &pos, &key, &value, &hash)) {
+            setentry an_entry;
 
-			an_entry.hash = hash;
-			an_entry.key = key;
-			rv = set_discard_entry(so, &an_entry);
-			if (rv == -1)
-				return NULL;
-			if (rv == DISCARD_NOTFOUND) {
-				if (set_add_entry(so, &an_entry) == -1)
-					return NULL;
-			}
-		}
-		Py_RETURN_NONE;
-	}
+            an_entry.hash = hash;
+            an_entry.key = key;
+            rv = set_discard_entry(so, &an_entry);
+            if (rv == -1)
+                return NULL;
+            if (rv == DISCARD_NOTFOUND) {
+                if (set_add_entry(so, &an_entry) == -1)
+                    return NULL;
+            }
+        }
+        Py_RETURN_NONE;
+    }
 
-	if (PyAnySet_Check(other)) {
-		Py_INCREF(other);
-		otherset = (PySetObject *)other;
-	} else {
-		otherset = (PySetObject *)make_new_set_basetype(Py_TYPE(so), other);
-		if (otherset == NULL)
-			return NULL;
-	}
+    if (PyAnySet_Check(other)) {
+        Py_INCREF(other);
+        otherset = (PySetObject *)other;
+    } else {
+        otherset = (PySetObject *)make_new_set_basetype(Py_TYPE(so), other);
+        if (otherset == NULL)
+            return NULL;
+    }
 
-	while (set_next(otherset, &pos, &entry)) {
-		int rv = set_discard_entry(so, entry);
-		if (rv == -1) {
-			Py_DECREF(otherset);
-			return NULL;
-		}
-		if (rv == DISCARD_NOTFOUND) {
-			if (set_add_entry(so, entry) == -1) {
-				Py_DECREF(otherset);
-				return NULL;
-			}
-		}
-	}
-	Py_DECREF(otherset);
-	Py_RETURN_NONE;
+    while (set_next(otherset, &pos, &entry)) {
+        int rv = set_discard_entry(so, entry);
+        if (rv == -1) {
+            Py_DECREF(otherset);
+            return NULL;
+        }
+        if (rv == DISCARD_NOTFOUND) {
+            if (set_add_entry(so, entry) == -1) {
+                Py_DECREF(otherset);
+                return NULL;
+            }
+        }
+    }
+    Py_DECREF(otherset);
+    Py_RETURN_NONE;
 }
 
 PyDoc_STRVAR(symmetric_difference_update_doc,
@@ -1687,17 +1687,17 @@
 static PyObject *
 set_symmetric_difference(PySetObject *so, PyObject *other)
 {
-	PyObject *rv;
-	PySetObject *otherset;
+    PyObject *rv;
+    PySetObject *otherset;
 
-	otherset = (PySetObject *)make_new_set_basetype(Py_TYPE(so), other);
-	if (otherset == NULL)
-		return NULL;
-	rv = set_symmetric_difference_update(otherset, (PyObject *)so);
-	if (rv == NULL)
-		return NULL;
-	Py_DECREF(rv);
-	return (PyObject *)otherset;
+    otherset = (PySetObject *)make_new_set_basetype(Py_TYPE(so), other);
+    if (otherset == NULL)
+        return NULL;
+    rv = set_symmetric_difference_update(otherset, (PyObject *)so);
+    if (rv == NULL)
+        return NULL;
+    Py_DECREF(rv);
+    return (PyObject *)otherset;
 }
 
 PyDoc_STRVAR(symmetric_difference_doc,
@@ -1708,56 +1708,56 @@
 static PyObject *
 set_xor(PySetObject *so, PyObject *other)
 {
-	if (!PyAnySet_Check(so) || !PyAnySet_Check(other)) {
-		Py_INCREF(Py_NotImplemented);
-		return Py_NotImplemented;
-	}
-	return set_symmetric_difference(so, other);
+    if (!PyAnySet_Check(so) || !PyAnySet_Check(other)) {
+        Py_INCREF(Py_NotImplemented);
+        return Py_NotImplemented;
+    }
+    return set_symmetric_difference(so, other);
 }
 
 static PyObject *
 set_ixor(PySetObject *so, PyObject *other)
 {
-	PyObject *result;
+    PyObject *result;
 
-	if (!PyAnySet_Check(other)) {
-		Py_INCREF(Py_NotImplemented);
-		return Py_NotImplemented;
-	}
-	result = set_symmetric_difference_update(so, other);
-	if (result == NULL)
-		return NULL;
-	Py_DECREF(result);
-	Py_INCREF(so);
-	return (PyObject *)so;
+    if (!PyAnySet_Check(other)) {
+        Py_INCREF(Py_NotImplemented);
+        return Py_NotImplemented;
+    }
+    result = set_symmetric_difference_update(so, other);
+    if (result == NULL)
+        return NULL;
+    Py_DECREF(result);
+    Py_INCREF(so);
+    return (PyObject *)so;
 }
 
 static PyObject *
 set_issubset(PySetObject *so, PyObject *other)
 {
-	setentry *entry;
-	Py_ssize_t pos = 0;
+    setentry *entry;
+    Py_ssize_t pos = 0;
 
-	if (!PyAnySet_Check(other)) {
-		PyObject *tmp, *result;
-		tmp = make_new_set(&PySet_Type, other);
-		if (tmp == NULL)
-			return NULL;
-		result = set_issubset(so, tmp);
-		Py_DECREF(tmp);
-		return result;
-	}
-	if (PySet_GET_SIZE(so) > PySet_GET_SIZE(other)) 
-		Py_RETURN_FALSE;
+    if (!PyAnySet_Check(other)) {
+        PyObject *tmp, *result;
+        tmp = make_new_set(&PySet_Type, other);
+        if (tmp == NULL)
+            return NULL;
+        result = set_issubset(so, tmp);
+        Py_DECREF(tmp);
+        return result;
+    }
+    if (PySet_GET_SIZE(so) > PySet_GET_SIZE(other))
+        Py_RETURN_FALSE;
 
-	while (set_next(so, &pos, &entry)) {
-		int rv = set_contains_entry((PySetObject *)other, entry);
-		if (rv == -1)
-			return NULL;
-		if (!rv)
-			Py_RETURN_FALSE;
-	}
-	Py_RETURN_TRUE;
+    while (set_next(so, &pos, &entry)) {
+        int rv = set_contains_entry((PySetObject *)other, entry);
+        if (rv == -1)
+            return NULL;
+        if (!rv)
+            Py_RETURN_FALSE;
+    }
+    Py_RETURN_TRUE;
 }
 
 PyDoc_STRVAR(issubset_doc, "Report whether another set contains this set.");
@@ -1765,17 +1765,17 @@
 static PyObject *
 set_issuperset(PySetObject *so, PyObject *other)
 {
-	PyObject *tmp, *result;
+    PyObject *tmp, *result;
 
-	if (!PyAnySet_Check(other)) {
-		tmp = make_new_set(&PySet_Type, other);
-		if (tmp == NULL)
-			return NULL;
-		result = set_issuperset(so, tmp);
-		Py_DECREF(tmp);
-		return result;
-	}
-	return set_issubset((PySetObject *)other, (PyObject *)so);
+    if (!PyAnySet_Check(other)) {
+        tmp = make_new_set(&PySet_Type, other);
+        if (tmp == NULL)
+            return NULL;
+        result = set_issuperset(so, tmp);
+        Py_DECREF(tmp);
+        return result;
+    }
+    return set_issubset((PySetObject *)other, (PyObject *)so);
 }
 
 PyDoc_STRVAR(issuperset_doc, "Report whether this set contains another set.");
@@ -1783,54 +1783,54 @@
 static PyObject *
 set_richcompare(PySetObject *v, PyObject *w, int op)
 {
-	PyObject *r1, *r2;
+    PyObject *r1, *r2;
 
-	if(!PyAnySet_Check(w)) {
-		Py_INCREF(Py_NotImplemented);
-		return Py_NotImplemented;
-	}
-	switch (op) {
-	case Py_EQ:
-		if (PySet_GET_SIZE(v) != PySet_GET_SIZE(w))
-			Py_RETURN_FALSE;
-		if (v->hash != -1  &&
-		    ((PySetObject *)w)->hash != -1 &&
-		    v->hash != ((PySetObject *)w)->hash)
-			Py_RETURN_FALSE;
-		return set_issubset(v, w);
-	case Py_NE:
-		r1 = set_richcompare(v, w, Py_EQ);
-		if (r1 == NULL)
-			return NULL;
-		r2 = PyBool_FromLong(PyObject_Not(r1));
-		Py_DECREF(r1);
-		return r2;
-	case Py_LE:
-		return set_issubset(v, w);
-	case Py_GE:
-		return set_issuperset(v, w);
-	case Py_LT:
-		if (PySet_GET_SIZE(v) >= PySet_GET_SIZE(w))
-			Py_RETURN_FALSE;		
-		return set_issubset(v, w);
-	case Py_GT:
-		if (PySet_GET_SIZE(v) <= PySet_GET_SIZE(w))
-			Py_RETURN_FALSE;
-		return set_issuperset(v, w);
-	}
-	Py_INCREF(Py_NotImplemented);
-	return Py_NotImplemented;
+    if(!PyAnySet_Check(w)) {
+        Py_INCREF(Py_NotImplemented);
+        return Py_NotImplemented;
+    }
+    switch (op) {
+    case Py_EQ:
+        if (PySet_GET_SIZE(v) != PySet_GET_SIZE(w))
+            Py_RETURN_FALSE;
+        if (v->hash != -1  &&
+            ((PySetObject *)w)->hash != -1 &&
+            v->hash != ((PySetObject *)w)->hash)
+            Py_RETURN_FALSE;
+        return set_issubset(v, w);
+    case Py_NE:
+        r1 = set_richcompare(v, w, Py_EQ);
+        if (r1 == NULL)
+            return NULL;
+        r2 = PyBool_FromLong(PyObject_Not(r1));
+        Py_DECREF(r1);
+        return r2;
+    case Py_LE:
+        return set_issubset(v, w);
+    case Py_GE:
+        return set_issuperset(v, w);
+    case Py_LT:
+        if (PySet_GET_SIZE(v) >= PySet_GET_SIZE(w))
+            Py_RETURN_FALSE;
+        return set_issubset(v, w);
+    case Py_GT:
+        if (PySet_GET_SIZE(v) <= PySet_GET_SIZE(w))
+            Py_RETURN_FALSE;
+        return set_issuperset(v, w);
+    }
+    Py_INCREF(Py_NotImplemented);
+    return Py_NotImplemented;
 }
 
 static PyObject *
 set_add(PySetObject *so, PyObject *key)
 {
-	if (set_add_key(so, key) == -1)
-		return NULL;
-	Py_RETURN_NONE;
+    if (set_add_key(so, key) == -1)
+        return NULL;
+    Py_RETURN_NONE;
 }
 
-PyDoc_STRVAR(add_doc, 
+PyDoc_STRVAR(add_doc,
 "Add an element to a set.\n\
 \n\
 This has no effect if the element is already present.");
@@ -1838,34 +1838,34 @@
 static int
 set_contains(PySetObject *so, PyObject *key)
 {
-	PyObject *tmpkey;
-	int rv;
+    PyObject *tmpkey;
+    int rv;
 
-	rv = set_contains_key(so, key);
-	if (rv == -1) {
-		if (!PySet_Check(key) || !PyErr_ExceptionMatches(PyExc_TypeError))
-			return -1;
-		PyErr_Clear();
-		tmpkey = make_new_set(&PyFrozenSet_Type, NULL);
-		if (tmpkey == NULL)
-			return -1;
-		set_swap_bodies((PySetObject *)tmpkey, (PySetObject *)key);
-		rv = set_contains(so, tmpkey);
-		set_swap_bodies((PySetObject *)tmpkey, (PySetObject *)key);
-		Py_DECREF(tmpkey);
-	}
-	return rv;
+    rv = set_contains_key(so, key);
+    if (rv == -1) {
+        if (!PySet_Check(key) || !PyErr_ExceptionMatches(PyExc_TypeError))
+            return -1;
+        PyErr_Clear();
+        tmpkey = make_new_set(&PyFrozenSet_Type, NULL);
+        if (tmpkey == NULL)
+            return -1;
+        set_swap_bodies((PySetObject *)tmpkey, (PySetObject *)key);
+        rv = set_contains(so, tmpkey);
+        set_swap_bodies((PySetObject *)tmpkey, (PySetObject *)key);
+        Py_DECREF(tmpkey);
+    }
+    return rv;
 }
 
 static PyObject *
 set_direct_contains(PySetObject *so, PyObject *key)
 {
-	long result;
+    long result;
 
-	result = set_contains(so, key);
-	if (result == -1)
-		return NULL;
-	return PyBool_FromLong(result);
+    result = set_contains(so, key);
+    if (result == -1)
+        return NULL;
+    return PyBool_FromLong(result);
 }
 
 PyDoc_STRVAR(contains_doc, "x.__contains__(y) <==> y in x.");
@@ -1873,30 +1873,30 @@
 static PyObject *
 set_remove(PySetObject *so, PyObject *key)
 {
-	PyObject *tmpkey;
-	int rv;
+    PyObject *tmpkey;
+    int rv;
 
-	rv = set_discard_key(so, key);
-	if (rv == -1) {
-		if (!PySet_Check(key) || !PyErr_ExceptionMatches(PyExc_TypeError))
-			return NULL;
-		PyErr_Clear();
-		tmpkey = make_new_set(&PyFrozenSet_Type, NULL);
-		if (tmpkey == NULL)
-			return NULL;
-		set_swap_bodies((PySetObject *)tmpkey, (PySetObject *)key);
-		rv = set_discard_key(so, tmpkey);
-		set_swap_bodies((PySetObject *)tmpkey, (PySetObject *)key);
-		Py_DECREF(tmpkey);
-		if (rv == -1)
-			return NULL;
-	} 
+    rv = set_discard_key(so, key);
+    if (rv == -1) {
+        if (!PySet_Check(key) || !PyErr_ExceptionMatches(PyExc_TypeError))
+            return NULL;
+        PyErr_Clear();
+        tmpkey = make_new_set(&PyFrozenSet_Type, NULL);
+        if (tmpkey == NULL)
+            return NULL;
+        set_swap_bodies((PySetObject *)tmpkey, (PySetObject *)key);
+        rv = set_discard_key(so, tmpkey);
+        set_swap_bodies((PySetObject *)tmpkey, (PySetObject *)key);
+        Py_DECREF(tmpkey);
+        if (rv == -1)
+            return NULL;
+    }
 
-	if (rv == DISCARD_NOTFOUND) {
-		set_key_error(key);
-		return NULL;
-	}
-	Py_RETURN_NONE;
+    if (rv == DISCARD_NOTFOUND) {
+        set_key_error(key);
+        return NULL;
+    }
+    Py_RETURN_NONE;
 }
 
 PyDoc_STRVAR(remove_doc,
@@ -1907,54 +1907,54 @@
 static PyObject *
 set_discard(PySetObject *so, PyObject *key)
 {
-	PyObject *tmpkey, *result;
-	int rv;
+    PyObject *tmpkey, *result;
+    int rv;
 
-	rv = set_discard_key(so, key);
-	if (rv == -1) {
-		if (!PySet_Check(key) || !PyErr_ExceptionMatches(PyExc_TypeError))
-			return NULL;
-		PyErr_Clear();
-		tmpkey = make_new_set(&PyFrozenSet_Type, NULL);
-		if (tmpkey == NULL)
-			return NULL;
-		set_swap_bodies((PySetObject *)tmpkey, (PySetObject *)key);
-		result = set_discard(so, tmpkey);
-		set_swap_bodies((PySetObject *)tmpkey, (PySetObject *)key);
-		Py_DECREF(tmpkey);
-		return result;
-	}
-	Py_RETURN_NONE;
+    rv = set_discard_key(so, key);
+    if (rv == -1) {
+        if (!PySet_Check(key) || !PyErr_ExceptionMatches(PyExc_TypeError))
+            return NULL;
+        PyErr_Clear();
+        tmpkey = make_new_set(&PyFrozenSet_Type, NULL);
+        if (tmpkey == NULL)
+            return NULL;
+        set_swap_bodies((PySetObject *)tmpkey, (PySetObject *)key);
+        result = set_discard(so, tmpkey);
+        set_swap_bodies((PySetObject *)tmpkey, (PySetObject *)key);
+        Py_DECREF(tmpkey);
+        return result;
+    }
+    Py_RETURN_NONE;
 }
 
 PyDoc_STRVAR(discard_doc,
 "Remove an element from a set if it is a member.\n\
 \n\
-If the element is not a member, do nothing."); 
+If the element is not a member, do nothing.");
 
 static PyObject *
 set_reduce(PySetObject *so)
 {
-	PyObject *keys=NULL, *args=NULL, *result=NULL, *dict=NULL;
+    PyObject *keys=NULL, *args=NULL, *result=NULL, *dict=NULL;
 
-	keys = PySequence_List((PyObject *)so);
-	if (keys == NULL)
-		goto done;
-	args = PyTuple_Pack(1, keys);
-	if (args == NULL)
-		goto done;
-	dict = PyObject_GetAttrString((PyObject *)so, "__dict__");
-	if (dict == NULL) {
-		PyErr_Clear();
-		dict = Py_None;
-		Py_INCREF(dict);
-	}
-	result = PyTuple_Pack(3, Py_TYPE(so), args, dict);
+    keys = PySequence_List((PyObject *)so);
+    if (keys == NULL)
+        goto done;
+    args = PyTuple_Pack(1, keys);
+    if (args == NULL)
+        goto done;
+    dict = PyObject_GetAttrString((PyObject *)so, "__dict__");
+    if (dict == NULL) {
+        PyErr_Clear();
+        dict = Py_None;
+        Py_INCREF(dict);
+    }
+    result = PyTuple_Pack(3, Py_TYPE(so), args, dict);
 done:
-	Py_XDECREF(args);
-	Py_XDECREF(keys);
-	Py_XDECREF(dict);
-	return result;
+    Py_XDECREF(args);
+    Py_XDECREF(keys);
+    Py_XDECREF(dict);
+    return result;
 }
 
 PyDoc_STRVAR(reduce_doc, "Return state information for pickling.");
@@ -1962,42 +1962,42 @@
 static PyObject *
 set_sizeof(PySetObject *so)
 {
-	Py_ssize_t res;
+    Py_ssize_t res;
 
-	res = sizeof(PySetObject);
-	if (so->table != so->smalltable)
-		res = res + (so->mask + 1) * sizeof(setentry);
-	return PyLong_FromSsize_t(res);
+    res = sizeof(PySetObject);
+    if (so->table != so->smalltable)
+        res = res + (so->mask + 1) * sizeof(setentry);
+    return PyLong_FromSsize_t(res);
 }
 
 PyDoc_STRVAR(sizeof_doc, "S.__sizeof__() -> size of S in memory, in bytes");
 static int
 set_init(PySetObject *self, PyObject *args, PyObject *kwds)
 {
-	PyObject *iterable = NULL;
+    PyObject *iterable = NULL;
 
-	if (!PyAnySet_Check(self))
-		return -1;
-	if (PySet_Check(self) && !_PyArg_NoKeywords("set()", kwds))
-		return -1;
-	if (!PyArg_UnpackTuple(args, Py_TYPE(self)->tp_name, 0, 1, &iterable))
-		return -1;
-	set_clear_internal(self);
-	self->hash = -1;
-	if (iterable == NULL)
-		return 0;
-	return set_update_internal(self, iterable);
+    if (!PyAnySet_Check(self))
+        return -1;
+    if (PySet_Check(self) && !_PyArg_NoKeywords("set()", kwds))
+        return -1;
+    if (!PyArg_UnpackTuple(args, Py_TYPE(self)->tp_name, 0, 1, &iterable))
+        return -1;
+    set_clear_internal(self);
+    self->hash = -1;
+    if (iterable == NULL)
+        return 0;
+    return set_update_internal(self, iterable);
 }
 
 static PySequenceMethods set_as_sequence = {
-	set_len,			/* sq_length */
-	0,				/* sq_concat */
-	0,				/* sq_repeat */
-	0,				/* sq_item */
-	0,				/* sq_slice */
-	0,				/* sq_ass_item */
-	0,				/* sq_ass_slice */
-	(objobjproc)set_contains,	/* sq_contains */
+    set_len,                            /* sq_length */
+    0,                                  /* sq_concat */
+    0,                                  /* sq_repeat */
+    0,                                  /* sq_item */
+    0,                                  /* sq_slice */
+    0,                                  /* sq_ass_item */
+    0,                                  /* sq_ass_slice */
+    (objobjproc)set_contains,           /* sq_contains */
 };
 
 /* set object ********************************************************/
@@ -2010,83 +2010,83 @@
 #endif
 
 static PyMethodDef set_methods[] = {
-	{"add",		(PyCFunction)set_add,		METH_O,
-	 add_doc},
-	{"clear",	(PyCFunction)set_clear,		METH_NOARGS,
-	 clear_doc},
-	{"__contains__",(PyCFunction)set_direct_contains,	METH_O | METH_COEXIST,
-	 contains_doc},
-	{"copy",	(PyCFunction)set_copy,		METH_NOARGS,
-	 copy_doc},
-	{"discard",	(PyCFunction)set_discard,	METH_O,
-	 discard_doc},
-	{"difference",	(PyCFunction)set_difference_multi,	METH_VARARGS,
-	 difference_doc},
-	{"difference_update",	(PyCFunction)set_difference_update,	METH_VARARGS,
-	 difference_update_doc},
-	{"intersection",(PyCFunction)set_intersection_multi,	METH_VARARGS,
-	 intersection_doc},
-	{"intersection_update",(PyCFunction)set_intersection_update_multi,	METH_VARARGS,
-	 intersection_update_doc},
-	{"isdisjoint",	(PyCFunction)set_isdisjoint,	METH_O,
-	 isdisjoint_doc},
-	{"issubset",	(PyCFunction)set_issubset,	METH_O,
-	 issubset_doc},
-	{"issuperset",	(PyCFunction)set_issuperset,	METH_O,
-	 issuperset_doc},
-	{"pop",		(PyCFunction)set_pop,		METH_NOARGS,
-	 pop_doc},
-	{"__reduce__",	(PyCFunction)set_reduce,	METH_NOARGS,
-	 reduce_doc},
-	{"remove",	(PyCFunction)set_remove,	METH_O,
-	 remove_doc},
-	{"__sizeof__",	(PyCFunction)set_sizeof,	METH_NOARGS,
-	 sizeof_doc},
-	{"symmetric_difference",(PyCFunction)set_symmetric_difference,	METH_O,
-	 symmetric_difference_doc},
-	{"symmetric_difference_update",(PyCFunction)set_symmetric_difference_update,	METH_O,
-	 symmetric_difference_update_doc},
+    {"add",             (PyCFunction)set_add,           METH_O,
+     add_doc},
+    {"clear",           (PyCFunction)set_clear,         METH_NOARGS,
+     clear_doc},
+    {"__contains__",(PyCFunction)set_direct_contains,           METH_O | METH_COEXIST,
+     contains_doc},
+    {"copy",            (PyCFunction)set_copy,          METH_NOARGS,
+     copy_doc},
+    {"discard",         (PyCFunction)set_discard,       METH_O,
+     discard_doc},
+    {"difference",      (PyCFunction)set_difference_multi,      METH_VARARGS,
+     difference_doc},
+    {"difference_update",       (PyCFunction)set_difference_update,     METH_VARARGS,
+     difference_update_doc},
+    {"intersection",(PyCFunction)set_intersection_multi,        METH_VARARGS,
+     intersection_doc},
+    {"intersection_update",(PyCFunction)set_intersection_update_multi,          METH_VARARGS,
+     intersection_update_doc},
+    {"isdisjoint",      (PyCFunction)set_isdisjoint,    METH_O,
+     isdisjoint_doc},
+    {"issubset",        (PyCFunction)set_issubset,      METH_O,
+     issubset_doc},
+    {"issuperset",      (PyCFunction)set_issuperset,    METH_O,
+     issuperset_doc},
+    {"pop",             (PyCFunction)set_pop,           METH_NOARGS,
+     pop_doc},
+    {"__reduce__",      (PyCFunction)set_reduce,        METH_NOARGS,
+     reduce_doc},
+    {"remove",          (PyCFunction)set_remove,        METH_O,
+     remove_doc},
+    {"__sizeof__",      (PyCFunction)set_sizeof,        METH_NOARGS,
+     sizeof_doc},
+    {"symmetric_difference",(PyCFunction)set_symmetric_difference,      METH_O,
+     symmetric_difference_doc},
+    {"symmetric_difference_update",(PyCFunction)set_symmetric_difference_update,        METH_O,
+     symmetric_difference_update_doc},
 #ifdef Py_DEBUG
-	{"test_c_api",	(PyCFunction)test_c_api,	METH_NOARGS,
-	 test_c_api_doc},
+    {"test_c_api",      (PyCFunction)test_c_api,        METH_NOARGS,
+     test_c_api_doc},
 #endif
-	{"union",	(PyCFunction)set_union,		METH_VARARGS,
-	 union_doc},
-	{"update",	(PyCFunction)set_update,	METH_VARARGS,
-	 update_doc},
-	{NULL,		NULL}	/* sentinel */
+    {"union",           (PyCFunction)set_union,         METH_VARARGS,
+     union_doc},
+    {"update",          (PyCFunction)set_update,        METH_VARARGS,
+     update_doc},
+    {NULL,              NULL}   /* sentinel */
 };
 
 static PyNumberMethods set_as_number = {
-	0,				/*nb_add*/
-	(binaryfunc)set_sub,		/*nb_subtract*/
-	0,				/*nb_multiply*/
-	0,				/*nb_remainder*/
-	0,				/*nb_divmod*/
-	0,				/*nb_power*/
-	0,				/*nb_negative*/
-	0,				/*nb_positive*/
-	0,				/*nb_absolute*/
-	0,				/*nb_bool*/
-	0,				/*nb_invert*/
-	0,				/*nb_lshift*/
-	0,				/*nb_rshift*/
-	(binaryfunc)set_and,		/*nb_and*/
-	(binaryfunc)set_xor,		/*nb_xor*/
-	(binaryfunc)set_or,		/*nb_or*/
-	0,				/*nb_int*/
-	0,				/*nb_reserved*/
-	0,				/*nb_float*/
-	0,				/*nb_inplace_add*/
-	(binaryfunc)set_isub,		/*nb_inplace_subtract*/
-	0,				/*nb_inplace_multiply*/
-	0,				/*nb_inplace_remainder*/
-	0,				/*nb_inplace_power*/
-	0,				/*nb_inplace_lshift*/
-	0,				/*nb_inplace_rshift*/
-	(binaryfunc)set_iand,		/*nb_inplace_and*/
-	(binaryfunc)set_ixor,		/*nb_inplace_xor*/
-	(binaryfunc)set_ior,		/*nb_inplace_or*/
+    0,                                  /*nb_add*/
+    (binaryfunc)set_sub,                /*nb_subtract*/
+    0,                                  /*nb_multiply*/
+    0,                                  /*nb_remainder*/
+    0,                                  /*nb_divmod*/
+    0,                                  /*nb_power*/
+    0,                                  /*nb_negative*/
+    0,                                  /*nb_positive*/
+    0,                                  /*nb_absolute*/
+    0,                                  /*nb_bool*/
+    0,                                  /*nb_invert*/
+    0,                                  /*nb_lshift*/
+    0,                                  /*nb_rshift*/
+    (binaryfunc)set_and,                /*nb_and*/
+    (binaryfunc)set_xor,                /*nb_xor*/
+    (binaryfunc)set_or,                 /*nb_or*/
+    0,                                  /*nb_int*/
+    0,                                  /*nb_reserved*/
+    0,                                  /*nb_float*/
+    0,                                  /*nb_inplace_add*/
+    (binaryfunc)set_isub,               /*nb_inplace_subtract*/
+    0,                                  /*nb_inplace_multiply*/
+    0,                                  /*nb_inplace_remainder*/
+    0,                                  /*nb_inplace_power*/
+    0,                                  /*nb_inplace_lshift*/
+    0,                                  /*nb_inplace_rshift*/
+    (binaryfunc)set_iand,               /*nb_inplace_and*/
+    (binaryfunc)set_ixor,               /*nb_inplace_xor*/
+    (binaryfunc)set_ior,                /*nb_inplace_or*/
 };
 
 PyDoc_STRVAR(set_doc,
@@ -2096,95 +2096,95 @@
 Build an unordered collection of unique elements.");
 
 PyTypeObject PySet_Type = {
-	PyVarObject_HEAD_INIT(&PyType_Type, 0)
-	"set",				/* tp_name */
-	sizeof(PySetObject),		/* tp_basicsize */
-	0,				/* tp_itemsize */
-	/* methods */
-	(destructor)set_dealloc,	/* tp_dealloc */
-	0,				/* tp_print */
-	0,				/* tp_getattr */
-	0,				/* tp_setattr */
-	0,				/* tp_reserved */
-	(reprfunc)set_repr,		/* tp_repr */
-	&set_as_number,			/* tp_as_number */
-	&set_as_sequence,		/* tp_as_sequence */
-	0,				/* tp_as_mapping */
-	(hashfunc)PyObject_HashNotImplemented,	/* tp_hash */
-	0,				/* tp_call */
-	0,				/* tp_str */
-	PyObject_GenericGetAttr,	/* tp_getattro */
-	0,				/* tp_setattro */
-	0,				/* tp_as_buffer */
-	Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC |
-		Py_TPFLAGS_BASETYPE,	/* tp_flags */
-	set_doc,			/* tp_doc */
-	(traverseproc)set_traverse,	/* tp_traverse */
-	(inquiry)set_clear_internal,	/* tp_clear */
-	(richcmpfunc)set_richcompare,	/* tp_richcompare */
-	offsetof(PySetObject, weakreflist),	/* tp_weaklistoffset */
-	(getiterfunc)set_iter,	/* tp_iter */
-	0,				/* tp_iternext */
-	set_methods,			/* tp_methods */
-	0,				/* tp_members */
-	0,				/* tp_getset */
-	0,				/* tp_base */
-	0,				/* tp_dict */
-	0,				/* tp_descr_get */
-	0,				/* tp_descr_set */
-	0,				/* tp_dictoffset */
-	(initproc)set_init,		/* tp_init */
-	PyType_GenericAlloc,		/* tp_alloc */
-	set_new,			/* tp_new */
-	PyObject_GC_Del,		/* tp_free */
+    PyVarObject_HEAD_INIT(&PyType_Type, 0)
+    "set",                              /* tp_name */
+    sizeof(PySetObject),                /* tp_basicsize */
+    0,                                  /* tp_itemsize */
+    /* methods */
+    (destructor)set_dealloc,            /* tp_dealloc */
+    0,                                  /* tp_print */
+    0,                                  /* tp_getattr */
+    0,                                  /* tp_setattr */
+    0,                                  /* tp_reserved */
+    (reprfunc)set_repr,                 /* tp_repr */
+    &set_as_number,                     /* tp_as_number */
+    &set_as_sequence,                   /* tp_as_sequence */
+    0,                                  /* tp_as_mapping */
+    (hashfunc)PyObject_HashNotImplemented,      /* tp_hash */
+    0,                                  /* tp_call */
+    0,                                  /* tp_str */
+    PyObject_GenericGetAttr,            /* tp_getattro */
+    0,                                  /* tp_setattro */
+    0,                                  /* tp_as_buffer */
+    Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC |
+        Py_TPFLAGS_BASETYPE,            /* tp_flags */
+    set_doc,                            /* tp_doc */
+    (traverseproc)set_traverse,         /* tp_traverse */
+    (inquiry)set_clear_internal,        /* tp_clear */
+    (richcmpfunc)set_richcompare,       /* tp_richcompare */
+    offsetof(PySetObject, weakreflist),         /* tp_weaklistoffset */
+    (getiterfunc)set_iter,      /* tp_iter */
+    0,                                  /* tp_iternext */
+    set_methods,                        /* tp_methods */
+    0,                                  /* tp_members */
+    0,                                  /* tp_getset */
+    0,                                  /* tp_base */
+    0,                                  /* tp_dict */
+    0,                                  /* tp_descr_get */
+    0,                                  /* tp_descr_set */
+    0,                                  /* tp_dictoffset */
+    (initproc)set_init,                 /* tp_init */
+    PyType_GenericAlloc,                /* tp_alloc */
+    set_new,                            /* tp_new */
+    PyObject_GC_Del,                    /* tp_free */
 };
 
 /* frozenset object ********************************************************/
 
 
 static PyMethodDef frozenset_methods[] = {
-	{"__contains__",(PyCFunction)set_direct_contains,	METH_O | METH_COEXIST,
-	 contains_doc},
-	{"copy",	(PyCFunction)frozenset_copy,	METH_NOARGS,
-	 copy_doc},
-	{"difference",	(PyCFunction)set_difference_multi,	METH_VARARGS,
-	 difference_doc},
-	{"intersection",(PyCFunction)set_intersection_multi,	METH_VARARGS,
-	 intersection_doc},
-	{"isdisjoint",	(PyCFunction)set_isdisjoint,	METH_O,
-	 isdisjoint_doc},
-	{"issubset",	(PyCFunction)set_issubset,	METH_O,
-	 issubset_doc},
-	{"issuperset",	(PyCFunction)set_issuperset,	METH_O,
-	 issuperset_doc},
-	{"__reduce__",	(PyCFunction)set_reduce,	METH_NOARGS,
-	 reduce_doc},
-	{"__sizeof__",	(PyCFunction)set_sizeof,	METH_NOARGS,
-	 sizeof_doc},
-	{"symmetric_difference",(PyCFunction)set_symmetric_difference,	METH_O,
-	 symmetric_difference_doc},
-	{"union",	(PyCFunction)set_union,		METH_VARARGS,
-	 union_doc},
-	{NULL,		NULL}	/* sentinel */
+    {"__contains__",(PyCFunction)set_direct_contains,           METH_O | METH_COEXIST,
+     contains_doc},
+    {"copy",            (PyCFunction)frozenset_copy,    METH_NOARGS,
+     copy_doc},
+    {"difference",      (PyCFunction)set_difference_multi,      METH_VARARGS,
+     difference_doc},
+    {"intersection",(PyCFunction)set_intersection_multi,        METH_VARARGS,
+     intersection_doc},
+    {"isdisjoint",      (PyCFunction)set_isdisjoint,    METH_O,
+     isdisjoint_doc},
+    {"issubset",        (PyCFunction)set_issubset,      METH_O,
+     issubset_doc},
+    {"issuperset",      (PyCFunction)set_issuperset,    METH_O,
+     issuperset_doc},
+    {"__reduce__",      (PyCFunction)set_reduce,        METH_NOARGS,
+     reduce_doc},
+    {"__sizeof__",      (PyCFunction)set_sizeof,        METH_NOARGS,
+     sizeof_doc},
+    {"symmetric_difference",(PyCFunction)set_symmetric_difference,      METH_O,
+     symmetric_difference_doc},
+    {"union",           (PyCFunction)set_union,         METH_VARARGS,
+     union_doc},
+    {NULL,              NULL}   /* sentinel */
 };
 
 static PyNumberMethods frozenset_as_number = {
-	0,				/*nb_add*/
-	(binaryfunc)set_sub,		/*nb_subtract*/
-	0,				/*nb_multiply*/
-	0,				/*nb_remainder*/
-	0,				/*nb_divmod*/
-	0,				/*nb_power*/
-	0,				/*nb_negative*/
-	0,				/*nb_positive*/
-	0,				/*nb_absolute*/
-	0,				/*nb_bool*/
-	0,				/*nb_invert*/
-	0,				/*nb_lshift*/
-	0,				/*nb_rshift*/
-	(binaryfunc)set_and,		/*nb_and*/
-	(binaryfunc)set_xor,		/*nb_xor*/
-	(binaryfunc)set_or,		/*nb_or*/
+    0,                                  /*nb_add*/
+    (binaryfunc)set_sub,                /*nb_subtract*/
+    0,                                  /*nb_multiply*/
+    0,                                  /*nb_remainder*/
+    0,                                  /*nb_divmod*/
+    0,                                  /*nb_power*/
+    0,                                  /*nb_negative*/
+    0,                                  /*nb_positive*/
+    0,                                  /*nb_absolute*/
+    0,                                  /*nb_bool*/
+    0,                                  /*nb_invert*/
+    0,                                  /*nb_lshift*/
+    0,                                  /*nb_rshift*/
+    (binaryfunc)set_and,                /*nb_and*/
+    (binaryfunc)set_xor,                /*nb_xor*/
+    (binaryfunc)set_or,                 /*nb_or*/
 };
 
 PyDoc_STRVAR(frozenset_doc,
@@ -2194,47 +2194,47 @@
 Build an immutable unordered collection of unique elements.");
 
 PyTypeObject PyFrozenSet_Type = {
-	PyVarObject_HEAD_INIT(&PyType_Type, 0)
-	"frozenset",			/* tp_name */
-	sizeof(PySetObject),		/* tp_basicsize */
-	0,				/* tp_itemsize */
-	/* methods */
-	(destructor)set_dealloc,	/* tp_dealloc */
-	0,				/* tp_print */
-	0,				/* tp_getattr */
-	0,				/* tp_setattr */
-	0,				/* tp_reserved */
-	(reprfunc)set_repr,		/* tp_repr */
-	&frozenset_as_number,		/* tp_as_number */
-	&set_as_sequence,		/* tp_as_sequence */
-	0,				/* tp_as_mapping */
-	frozenset_hash,			/* tp_hash */
-	0,				/* tp_call */
-	0,				/* tp_str */
-	PyObject_GenericGetAttr,	/* tp_getattro */
-	0,				/* tp_setattro */
-	0,				/* tp_as_buffer */
-	Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC |
-		Py_TPFLAGS_BASETYPE,	/* tp_flags */
-	frozenset_doc,			/* tp_doc */
-	(traverseproc)set_traverse,	/* tp_traverse */
-	(inquiry)set_clear_internal,	/* tp_clear */
-	(richcmpfunc)set_richcompare,	/* tp_richcompare */
-	offsetof(PySetObject, weakreflist),	/* tp_weaklistoffset */
-	(getiterfunc)set_iter,		/* tp_iter */
-	0,				/* tp_iternext */
-	frozenset_methods,		/* tp_methods */
-	0,				/* tp_members */
-	0,				/* tp_getset */
-	0,				/* tp_base */
-	0,				/* tp_dict */
-	0,				/* tp_descr_get */
-	0,				/* tp_descr_set */
-	0,				/* tp_dictoffset */
-	0,				/* tp_init */
-	PyType_GenericAlloc,		/* tp_alloc */
-	frozenset_new,			/* tp_new */
-	PyObject_GC_Del,		/* tp_free */
+    PyVarObject_HEAD_INIT(&PyType_Type, 0)
+    "frozenset",                        /* tp_name */
+    sizeof(PySetObject),                /* tp_basicsize */
+    0,                                  /* tp_itemsize */
+    /* methods */
+    (destructor)set_dealloc,            /* tp_dealloc */
+    0,                                  /* tp_print */
+    0,                                  /* tp_getattr */
+    0,                                  /* tp_setattr */
+    0,                                  /* tp_reserved */
+    (reprfunc)set_repr,                 /* tp_repr */
+    &frozenset_as_number,               /* tp_as_number */
+    &set_as_sequence,                   /* tp_as_sequence */
+    0,                                  /* tp_as_mapping */
+    frozenset_hash,                     /* tp_hash */
+    0,                                  /* tp_call */
+    0,                                  /* tp_str */
+    PyObject_GenericGetAttr,            /* tp_getattro */
+    0,                                  /* tp_setattro */
+    0,                                  /* tp_as_buffer */
+    Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC |
+        Py_TPFLAGS_BASETYPE,            /* tp_flags */
+    frozenset_doc,                      /* tp_doc */
+    (traverseproc)set_traverse,         /* tp_traverse */
+    (inquiry)set_clear_internal,        /* tp_clear */
+    (richcmpfunc)set_richcompare,       /* tp_richcompare */
+    offsetof(PySetObject, weakreflist),         /* tp_weaklistoffset */
+    (getiterfunc)set_iter,              /* tp_iter */
+    0,                                  /* tp_iternext */
+    frozenset_methods,                  /* tp_methods */
+    0,                                  /* tp_members */
+    0,                                  /* tp_getset */
+    0,                                  /* tp_base */
+    0,                                  /* tp_dict */
+    0,                                  /* tp_descr_get */
+    0,                                  /* tp_descr_set */
+    0,                                  /* tp_dictoffset */
+    0,                                  /* tp_init */
+    PyType_GenericAlloc,                /* tp_alloc */
+    frozenset_new,                      /* tp_new */
+    PyObject_GC_Del,                    /* tp_free */
 };
 
 
@@ -2243,238 +2243,238 @@
 PyObject *
 PySet_New(PyObject *iterable)
 {
-	return make_new_set(&PySet_Type, iterable);
+    return make_new_set(&PySet_Type, iterable);
 }
 
 PyObject *
 PyFrozenSet_New(PyObject *iterable)
 {
-	return make_new_set(&PyFrozenSet_Type, iterable);
+    return make_new_set(&PyFrozenSet_Type, iterable);
 }
 
 Py_ssize_t
 PySet_Size(PyObject *anyset)
 {
-	if (!PyAnySet_Check(anyset)) {
-		PyErr_BadInternalCall();
-		return -1;
-	}
-	return PySet_GET_SIZE(anyset);
+    if (!PyAnySet_Check(anyset)) {
+        PyErr_BadInternalCall();
+        return -1;
+    }
+    return PySet_GET_SIZE(anyset);
 }
 
 int
 PySet_Clear(PyObject *set)
 {
-	if (!PySet_Check(set)) {
-		PyErr_BadInternalCall();
-		return -1;
-	}
-	return set_clear_internal((PySetObject *)set);
+    if (!PySet_Check(set)) {
+        PyErr_BadInternalCall();
+        return -1;
+    }
+    return set_clear_internal((PySetObject *)set);
 }
 
 int
 PySet_Contains(PyObject *anyset, PyObject *key)
 {
-	if (!PyAnySet_Check(anyset)) {
-		PyErr_BadInternalCall();
-		return -1;
-	}
-	return set_contains_key((PySetObject *)anyset, key);
+    if (!PyAnySet_Check(anyset)) {
+        PyErr_BadInternalCall();
+        return -1;
+    }
+    return set_contains_key((PySetObject *)anyset, key);
 }
 
 int
 PySet_Discard(PyObject *set, PyObject *key)
 {
-	if (!PySet_Check(set)) {
-		PyErr_BadInternalCall();
-		return -1;
-	}
-	return set_discard_key((PySetObject *)set, key);
+    if (!PySet_Check(set)) {
+        PyErr_BadInternalCall();
+        return -1;
+    }
+    return set_discard_key((PySetObject *)set, key);
 }
 
 int
 PySet_Add(PyObject *anyset, PyObject *key)
 {
-	if (!PySet_Check(anyset) && 
-	    (!PyFrozenSet_Check(anyset) || Py_REFCNT(anyset) != 1)) {
-		PyErr_BadInternalCall();
-		return -1;
-	}
-	return set_add_key((PySetObject *)anyset, key);
+    if (!PySet_Check(anyset) &&
+        (!PyFrozenSet_Check(anyset) || Py_REFCNT(anyset) != 1)) {
+        PyErr_BadInternalCall();
+        return -1;
+    }
+    return set_add_key((PySetObject *)anyset, key);
 }
 
 int
 _PySet_NextEntry(PyObject *set, Py_ssize_t *pos, PyObject **key, long *hash)
 {
-	setentry *entry;
+    setentry *entry;
 
-	if (!PyAnySet_Check(set)) {
-		PyErr_BadInternalCall();
-		return -1;
-	}
-	if (set_next((PySetObject *)set, pos, &entry) == 0)
-		return 0;
-	*key = entry->key;
-	*hash = entry->hash;
-	return 1;
+    if (!PyAnySet_Check(set)) {
+        PyErr_BadInternalCall();
+        return -1;
+    }
+    if (set_next((PySetObject *)set, pos, &entry) == 0)
+        return 0;
+    *key = entry->key;
+    *hash = entry->hash;
+    return 1;
 }
 
 PyObject *
 PySet_Pop(PyObject *set)
 {
-	if (!PySet_Check(set)) {
-		PyErr_BadInternalCall();
-		return NULL;
-	}
-	return set_pop((PySetObject *)set);
+    if (!PySet_Check(set)) {
+        PyErr_BadInternalCall();
+        return NULL;
+    }
+    return set_pop((PySetObject *)set);
 }
 
 int
 _PySet_Update(PyObject *set, PyObject *iterable)
 {
-	if (!PySet_Check(set)) {
-		PyErr_BadInternalCall();
-		return -1;
-	}
-	return set_update_internal((PySetObject *)set, iterable);
+    if (!PySet_Check(set)) {
+        PyErr_BadInternalCall();
+        return -1;
+    }
+    return set_update_internal((PySetObject *)set, iterable);
 }
 
 #ifdef Py_DEBUG
 
-/* Test code to be called with any three element set. 
+/* Test code to be called with any three element set.
    Returns True and original set is restored. */
 
-#define assertRaises(call_return_value, exception)		\
-	do {							\
-		assert(call_return_value);			\
-		assert(PyErr_ExceptionMatches(exception));	\
-		PyErr_Clear();					\
-	} while(0)
+#define assertRaises(call_return_value, exception)              \
+    do {                                                        \
+        assert(call_return_value);                              \
+        assert(PyErr_ExceptionMatches(exception));              \
+        PyErr_Clear();                                          \
+    } while(0)
 
 static PyObject *
 test_c_api(PySetObject *so)
 {
-	Py_ssize_t count;
-	char *s;
-	Py_ssize_t i;
-	PyObject *elem=NULL, *dup=NULL, *t, *f, *dup2, *x;
-	PyObject *ob = (PyObject *)so;
-	long hash;
-	PyObject *str;
+    Py_ssize_t count;
+    char *s;
+    Py_ssize_t i;
+    PyObject *elem=NULL, *dup=NULL, *t, *f, *dup2, *x;
+    PyObject *ob = (PyObject *)so;
+    long hash;
+    PyObject *str;
 
-	/* Verify preconditions */
-	assert(PyAnySet_Check(ob));
-	assert(PyAnySet_CheckExact(ob));
-	assert(!PyFrozenSet_CheckExact(ob));
+    /* Verify preconditions */
+    assert(PyAnySet_Check(ob));
+    assert(PyAnySet_CheckExact(ob));
+    assert(!PyFrozenSet_CheckExact(ob));
 
-	/* so.clear(); so |= set("abc"); */
-	str = PyUnicode_FromString("abc");
-	if (str == NULL)
-		return NULL;
-	set_clear_internal(so);
-	if (set_update_internal(so, str) == -1) {
-		Py_DECREF(str);
-		return NULL;
-	}
-	Py_DECREF(str);
+    /* so.clear(); so |= set("abc"); */
+    str = PyUnicode_FromString("abc");
+    if (str == NULL)
+        return NULL;
+    set_clear_internal(so);
+    if (set_update_internal(so, str) == -1) {
+        Py_DECREF(str);
+        return NULL;
+    }
+    Py_DECREF(str);
 
-	/* Exercise type/size checks */
-	assert(PySet_Size(ob) == 3);
-	assert(PySet_GET_SIZE(ob) == 3);
+    /* Exercise type/size checks */
+    assert(PySet_Size(ob) == 3);
+    assert(PySet_GET_SIZE(ob) == 3);
 
-	/* Raise TypeError for non-iterable constructor arguments */
-	assertRaises(PySet_New(Py_None) == NULL, PyExc_TypeError);
-	assertRaises(PyFrozenSet_New(Py_None) == NULL, PyExc_TypeError);
+    /* Raise TypeError for non-iterable constructor arguments */
+    assertRaises(PySet_New(Py_None) == NULL, PyExc_TypeError);
+    assertRaises(PyFrozenSet_New(Py_None) == NULL, PyExc_TypeError);
 
-	/* Raise TypeError for unhashable key */
-	dup = PySet_New(ob);
-	assertRaises(PySet_Discard(ob, dup) == -1, PyExc_TypeError);
-	assertRaises(PySet_Contains(ob, dup) == -1, PyExc_TypeError);
-	assertRaises(PySet_Add(ob, dup) == -1, PyExc_TypeError);
+    /* Raise TypeError for unhashable key */
+    dup = PySet_New(ob);
+    assertRaises(PySet_Discard(ob, dup) == -1, PyExc_TypeError);
+    assertRaises(PySet_Contains(ob, dup) == -1, PyExc_TypeError);
+    assertRaises(PySet_Add(ob, dup) == -1, PyExc_TypeError);
 
-	/* Exercise successful pop, contains, add, and discard */
-	elem = PySet_Pop(ob);
-	assert(PySet_Contains(ob, elem) == 0);
-	assert(PySet_GET_SIZE(ob) == 2);
-	assert(PySet_Add(ob, elem) == 0);
-	assert(PySet_Contains(ob, elem) == 1);
-	assert(PySet_GET_SIZE(ob) == 3);
-	assert(PySet_Discard(ob, elem) == 1);
-	assert(PySet_GET_SIZE(ob) == 2);
-	assert(PySet_Discard(ob, elem) == 0);
-	assert(PySet_GET_SIZE(ob) == 2);
+    /* Exercise successful pop, contains, add, and discard */
+    elem = PySet_Pop(ob);
+    assert(PySet_Contains(ob, elem) == 0);
+    assert(PySet_GET_SIZE(ob) == 2);
+    assert(PySet_Add(ob, elem) == 0);
+    assert(PySet_Contains(ob, elem) == 1);
+    assert(PySet_GET_SIZE(ob) == 3);
+    assert(PySet_Discard(ob, elem) == 1);
+    assert(PySet_GET_SIZE(ob) == 2);
+    assert(PySet_Discard(ob, elem) == 0);
+    assert(PySet_GET_SIZE(ob) == 2);
 
-	/* Exercise clear */
-	dup2 = PySet_New(dup);
-	assert(PySet_Clear(dup2) == 0);
-	assert(PySet_Size(dup2) == 0);
-	Py_DECREF(dup2);
+    /* Exercise clear */
+    dup2 = PySet_New(dup);
+    assert(PySet_Clear(dup2) == 0);
+    assert(PySet_Size(dup2) == 0);
+    Py_DECREF(dup2);
 
-	/* Raise SystemError on clear or update of frozen set */
-	f = PyFrozenSet_New(dup);
-	assertRaises(PySet_Clear(f) == -1, PyExc_SystemError);
-	assertRaises(_PySet_Update(f, dup) == -1, PyExc_SystemError);
-	assert(PySet_Add(f, elem) == 0);
-	Py_INCREF(f);
-	assertRaises(PySet_Add(f, elem) == -1, PyExc_SystemError);
-	Py_DECREF(f);
-	Py_DECREF(f);
+    /* Raise SystemError on clear or update of frozen set */
+    f = PyFrozenSet_New(dup);
+    assertRaises(PySet_Clear(f) == -1, PyExc_SystemError);
+    assertRaises(_PySet_Update(f, dup) == -1, PyExc_SystemError);
+    assert(PySet_Add(f, elem) == 0);
+    Py_INCREF(f);
+    assertRaises(PySet_Add(f, elem) == -1, PyExc_SystemError);
+    Py_DECREF(f);
+    Py_DECREF(f);
 
-	/* Exercise direct iteration */
-	i = 0, count = 0;
-	while (_PySet_NextEntry((PyObject *)dup, &i, &x, &hash)) {
-		s = _PyUnicode_AsString(x);
-		assert(s && (s[0] == 'a' || s[0] == 'b' || s[0] == 'c'));
-		count++;
-	}
-	assert(count == 3);
+    /* Exercise direct iteration */
+    i = 0, count = 0;
+    while (_PySet_NextEntry((PyObject *)dup, &i, &x, &hash)) {
+        s = _PyUnicode_AsString(x);
+        assert(s && (s[0] == 'a' || s[0] == 'b' || s[0] == 'c'));
+        count++;
+    }
+    assert(count == 3);
 
-	/* Exercise updates */
-	dup2 = PySet_New(NULL);
-	assert(_PySet_Update(dup2, dup) == 0);
-	assert(PySet_Size(dup2) == 3);
-	assert(_PySet_Update(dup2, dup) == 0);
-	assert(PySet_Size(dup2) == 3);
-	Py_DECREF(dup2);
+    /* Exercise updates */
+    dup2 = PySet_New(NULL);
+    assert(_PySet_Update(dup2, dup) == 0);
+    assert(PySet_Size(dup2) == 3);
+    assert(_PySet_Update(dup2, dup) == 0);
+    assert(PySet_Size(dup2) == 3);
+    Py_DECREF(dup2);
 
-	/* Raise SystemError when self argument is not a set or frozenset. */
-	t = PyTuple_New(0);
-	assertRaises(PySet_Size(t) == -1, PyExc_SystemError);
-	assertRaises(PySet_Contains(t, elem) == -1, PyExc_SystemError);
-	Py_DECREF(t);
+    /* Raise SystemError when self argument is not a set or frozenset. */
+    t = PyTuple_New(0);
+    assertRaises(PySet_Size(t) == -1, PyExc_SystemError);
+    assertRaises(PySet_Contains(t, elem) == -1, PyExc_SystemError);
+    Py_DECREF(t);
 
-	/* Raise SystemError when self argument is not a set. */
-	f = PyFrozenSet_New(dup);
-	assert(PySet_Size(f) == 3);
-	assert(PyFrozenSet_CheckExact(f));
-	assertRaises(PySet_Discard(f, elem) == -1, PyExc_SystemError);
-	assertRaises(PySet_Pop(f) == NULL, PyExc_SystemError);
-	Py_DECREF(f);
+    /* Raise SystemError when self argument is not a set. */
+    f = PyFrozenSet_New(dup);
+    assert(PySet_Size(f) == 3);
+    assert(PyFrozenSet_CheckExact(f));
+    assertRaises(PySet_Discard(f, elem) == -1, PyExc_SystemError);
+    assertRaises(PySet_Pop(f) == NULL, PyExc_SystemError);
+    Py_DECREF(f);
 
-	/* Raise KeyError when popping from an empty set */
-	assert(PyNumber_InPlaceSubtract(ob, ob) == ob);
-	Py_DECREF(ob);
-	assert(PySet_GET_SIZE(ob) == 0);
-	assertRaises(PySet_Pop(ob) == NULL, PyExc_KeyError);
+    /* Raise KeyError when popping from an empty set */
+    assert(PyNumber_InPlaceSubtract(ob, ob) == ob);
+    Py_DECREF(ob);
+    assert(PySet_GET_SIZE(ob) == 0);
+    assertRaises(PySet_Pop(ob) == NULL, PyExc_KeyError);
 
-	/* Restore the set from the copy using the PyNumber API */
-	assert(PyNumber_InPlaceOr(ob, dup) == ob);
-	Py_DECREF(ob);
+    /* Restore the set from the copy using the PyNumber API */
+    assert(PyNumber_InPlaceOr(ob, dup) == ob);
+    Py_DECREF(ob);
 
-	/* Verify constructors accept NULL arguments */
-	f = PySet_New(NULL);
-	assert(f != NULL);
-	assert(PySet_GET_SIZE(f) == 0);
-	Py_DECREF(f);
-	f = PyFrozenSet_New(NULL);
-	assert(f != NULL);
-	assert(PyFrozenSet_CheckExact(f));
-	assert(PySet_GET_SIZE(f) == 0);
-	Py_DECREF(f);
+    /* Verify constructors accept NULL arguments */
+    f = PySet_New(NULL);
+    assert(f != NULL);
+    assert(PySet_GET_SIZE(f) == 0);
+    Py_DECREF(f);
+    f = PyFrozenSet_New(NULL);
+    assert(f != NULL);
+    assert(PyFrozenSet_CheckExact(f));
+    assert(PySet_GET_SIZE(f) == 0);
+    Py_DECREF(f);
 
-	Py_DECREF(elem);
-	Py_DECREF(dup);
-	Py_RETURN_TRUE;
+    Py_DECREF(elem);
+    Py_DECREF(dup);
+    Py_RETURN_TRUE;
 }
 
 #undef assertRaises