Merged revisions 75714 via svnmerge from

svn+ssh://pythondev@svn.python.org/python/trunk

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  r75714 | mark.dickinson | 2009-10-26 14:18:44 +0000 (Mon, 26 Oct 2009) | 1 line

  Warn against replacing PyNumber_Add with PyNumber_InPlaceAdd in sum
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