Blocked revisions 81541 via svnmerge

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  r81541 | mark.dickinson | 2010-05-26 17:02:59 +0100 (Wed, 26 May 2010) | 4 lines

  Issue #8817: Expose round-to-nearest variant of divmod in _PyLong_Divmod_Near
  for use by the datetime module; also refactor long_round to use this function.
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