Added zip, map, filter to future_bultins (#2171)
diff --git a/Modules/itertoolsmodule.c b/Modules/itertoolsmodule.c
index 8c3375a..a369dc9 100644
--- a/Modules/itertoolsmodule.c
+++ b/Modules/itertoolsmodule.c
@@ -2542,7 +2542,7 @@
 	ifilterobject *lz;
 
 	if (Py_Py3kWarningFlag &&
-	    PyErr_Warn(PyExc_DeprecationWarning, 
+	    PyErr_Warn(PyExc_DeprecationWarning,
 		       "In 3.x, itertools.ifilter() was moved to builtin filter().") < 0)
 		return NULL;
 
@@ -2552,6 +2552,15 @@
 	if (!PyArg_UnpackTuple(args, "ifilter", 2, 2, &func, &seq))
 		return NULL;
 
+	if (func == Py_None) {
+		if (Py_Py3kWarningFlag &&
+		    PyErr_Warn(PyExc_DeprecationWarning,
+			       "ifilter with None as a first argument "
+			       "is not supported in 3.x.  Use a list "
+			       "comprehension instead.") < 0)
+			return NULL;
+	}
+
 	/* Get iterator. */
 	it = PyObject_GetIter(seq);
 	if (it == NULL)
@@ -3602,7 +3611,7 @@
 		&izip_type,
 		&iziplongest_type,
 		&permutations_type,
-		&product_type,         
+		&product_type,
 		&repeat_type,
 		&groupby_type,
 		NULL