Blocked revisions 70489 via svnmerge

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  r70489 | mark.dickinson | 2009-03-20 23:16:14 +0000 (Fri, 20 Mar 2009) | 4 lines

  Rewrite Py_ARITHMETIC_RIGHT_SHIFT so that it's valid for all signed
  integer types T, not just those for which "unsigned T" is legal.
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