Merged revisions 69481 via svnmerge from

svn+ssh://pythondev@svn.python.org/python/trunk

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  r69481 | brett.cannon | 2009-02-09 18:07:38 -0800 (Mon, 09 Feb 2009) | 4 lines

  compileall used the ctime of bytecode and source to determine if the bytecode
  should be recreated. This created a timing hole. Fixed by just doing what
  import does; check the mtime and magic number.
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