Blocked revisions 79662,79737 via svnmerge

Blocked revisions 79662,79737 via svnmerge

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  r79662 | raymond.hettinger | 2010-04-03 13:32:58 +0300 (Sat, 03 Apr 2010) | 1 line

  Add a subtract() method to collections.Counter()
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  r79737 | ezio.melotti | 2010-04-04 09:53:44 +0300 (Sun, 04 Apr 2010) | 13 lines

  Merged revisions 79733,79735 via svnmerge from
  svn+ssh://pythondev@svn.python.org/python/trunk

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    r79733 | ezio.melotti | 2010-04-04 09:41:27 +0300 (Sun, 04 Apr 2010) | 1 line

    Add a versionadded to Counter.subtract() doc.
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    r79735 | ezio.melotti | 2010-04-04 09:50:58 +0300 (Sun, 04 Apr 2010) | 1 line

    Revert 79733 - Counter is new in 2.7, the versionadded is not necessary - and fix a typo.
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