fix contextlib.ExitStack typo in 3.3's whatsnew.rst
diff --git a/Doc/whatsnew/3.3.rst b/Doc/whatsnew/3.3.rst
index c1c6642..8208f07 100644
--- a/Doc/whatsnew/3.3.rst
+++ b/Doc/whatsnew/3.3.rst
@@ -1079,7 +1079,7 @@
contextlib
----------
-:class:`~collections.ExitStack` now provides a solid foundation for
+:class:`~contextlib.ExitStack` now provides a solid foundation for
programmatic manipulation of context managers and similar cleanup
functionality. Unlike the previous ``contextlib.nested`` API (which was
deprecated and removed), the new API is designed to work correctly