Issue #7105:  weak dict iterators are fragile because of unpredictable GC runs
Backport the fix from pyton 3.x for this issue.
diff --git a/Doc/library/weakref.rst b/Doc/library/weakref.rst
index 950266e..1c3cdbb 100644
--- a/Doc/library/weakref.rst
+++ b/Doc/library/weakref.rst
@@ -163,7 +163,7 @@
 
 .. method:: WeakKeyDictionary.iterkeyrefs()
 
-   Return an :term:`iterator` that yields the weak references to the keys.
+   Return an iterable of the weak references to the keys.
 
    .. versionadded:: 2.5
 
@@ -195,7 +195,7 @@
 
 .. method:: WeakValueDictionary.itervaluerefs()
 
-   Return an :term:`iterator` that yields the weak references to the values.
+   Return an iterable of the weak references to the values.
 
    .. versionadded:: 2.5