Make readonly members defined in C throw an AttributeError on modification. This brings them into sync with Python-level attributes. Fixes bug #1687163.
diff --git a/Lib/test/test_csv.py b/Lib/test/test_csv.py
index 46361c8..2cdc807 100644
--- a/Lib/test/test_csv.py
+++ b/Lib/test/test_csv.py
@@ -53,8 +53,8 @@
         self.assertEqual(obj.dialect.skipinitialspace, False)
         self.assertEqual(obj.dialect.strict, False)
         # Try deleting or changing attributes (they are read-only)
-        self.assertRaises(TypeError, delattr, obj.dialect, 'delimiter')
-        self.assertRaises(TypeError, setattr, obj.dialect, 'delimiter', ':')
+        self.assertRaises(AttributeError, delattr, obj.dialect, 'delimiter')
+        self.assertRaises(AttributeError, setattr, obj.dialect, 'delimiter', ':')
         self.assertRaises(AttributeError, delattr, obj.dialect, 'quoting')
         self.assertRaises(AttributeError, setattr, obj.dialect,
                           'quoting', None)
diff --git a/Lib/test/test_descr.py b/Lib/test/test_descr.py
index 6cd8ccd..eec4e40 100644
--- a/Lib/test/test_descr.py
+++ b/Lib/test/test_descr.py
@@ -1857,13 +1857,13 @@
     for attr in "__doc__", "fget", "fset", "fdel":
         try:
             setattr(raw, attr, 42)
-        except TypeError as msg:
+        except AttributeError as msg:
             if str(msg).find('readonly') < 0:
                 raise TestFailed("when setting readonly attr %r on a "
-                                 "property, got unexpected TypeError "
+                                 "property, got unexpected AttributeError "
                                  "msg %r" % (attr, str(msg)))
         else:
-            raise TestFailed("expected TypeError from trying to set "
+            raise TestFailed("expected AttributeError from trying to set "
                              "readonly %r attr on a property" % attr)
 
     class D(object):
diff --git a/Lib/test/test_generators.py b/Lib/test/test_generators.py
index 7999034..12276be 100644
--- a/Lib/test/test_generators.py
+++ b/Lib/test/test_generators.py
@@ -400,7 +400,7 @@
 >>> i.gi_running = 42
 Traceback (most recent call last):
   ...
-TypeError: readonly attribute
+AttributeError: readonly attribute
 >>> def g():
 ...     yield me.gi_running
 >>> me = g()
diff --git a/Lib/test/test_os.py b/Lib/test/test_os.py
index 93e530c..a7fc1da 100644
--- a/Lib/test/test_os.py
+++ b/Lib/test/test_os.py
@@ -143,7 +143,7 @@
         try:
             result.st_mode = 1
             self.fail("No exception thrown")
-        except TypeError:
+        except AttributeError:
             pass
 
         try:
@@ -201,7 +201,7 @@
         try:
             result.f_bfree = 1
             self.fail("No exception thrown")
-        except TypeError:
+        except AttributeError:
             pass
 
         try: