Merged revisions 64549 via svnmerge from

Merged revisions 64549 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk

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  r64549 | brett.cannon | 2008-06-26 17:31:13 -0700 (Thu, 26 Jun 2008) | 7 lines

  warnings.warn_explicit() did not have the proper TypeErrors in place to prevent
  bus errors or SystemError being raised. As a side effect of fixing this, a bad
  DECREF that could be triggered when 'message' and 'category' were both None was
  fixed.

  Closes issue 3211. Thanks JP Calderone for the bug report.
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