(issue 7413 does not concern py3k, I merge the test nonetheless)

Merged revisions 77122 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk

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  r77122 | amaury.forgeotdarc | 2009-12-29 23:03:38 +0100 (mar., 29 déc. 2009) | 3 lines

  #7413: Passing '\0' as the separator to datetime.datetime.isoformat()
  used to drop the time part of the result.
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