Merged revisions 82587 via svnmerge from

svn+ssh://pythondev@svn.python.org/python/branches/py3k

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  r82587 | georg.brandl | 2010-07-05 19:48:38 +0200 (Mo, 05 Jul 2010) | 1 line

  #9166: NotImplemented is not an exception.
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Doc/whatsnew/2.7.rst

@@ -1073,7 +1073,7 @@ changes, or look through the Subversion logs for all the details.
   (Added by Raymond Hettinger; :issue:`1818`.)
 
   Finally, the :class:`~collections.Mapping` abstract base class now
-  raises a :exc:`NotImplemented` exception if a mapping is compared to
+  returns :const:`NotImplemented` if a mapping is compared to
   another type that isn't a :class:`Mapping`.
   (Fixed by Daniel Stutzbach; :issue:`8729`.)