http://svn.python.org/projects/python/trunk

Note that the performance improvement for the py3k branch is not as high as for trunk.

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  r72909 | collin.winter | 2009-05-24 21:34:39 -0700 (Sun, 24 May 2009) | 2 lines

  Issue 5670: special-case pickling of dicts. This nearly doubles the performance of dict pickling in cPickle.
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