Actually import itertools.
diff --git a/Lib/_abcoll.py b/Lib/_abcoll.py
index d25d521..b8f6fb9 100644
--- a/Lib/_abcoll.py
+++ b/Lib/_abcoll.py
@@ -9,6 +9,7 @@
 """
 
 from abc import ABCMeta, abstractmethod
+import itertools
 
 __all__ = ["Hashable", "Iterable", "Iterator",
            "Sized", "Container", "Callable",