Merge 3.5
diff --git a/Doc/whatsnew/3.5.rst b/Doc/whatsnew/3.5.rst
index 0abdc3f..10a9a2b 100644
--- a/Doc/whatsnew/3.5.rst
+++ b/Doc/whatsnew/3.5.rst
@@ -97,6 +97,10 @@
Significantly Improved Library Modules:
+* :class:`collections.OrderedDict` is now implemented in C, which improves
+ its performance between 4x to 100x times. Contributed by Eric Snow in
+ :issue:`16991`.
+
* You may now pass bytes to the :mod:`tempfile` module's APIs and it will
return the temporary pathname as bytes instead of str. It also accepts
a value of ``None`` on parameters where only str was accepted in the past to