Merged revisions 70992,70995 via svnmerge from

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

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  r70992 | georg.brandl | 2009-04-01 16:00:55 -0500 (Wed, 01 Apr 2009) | 1 line

  #4572: add SEEK_* values as constants in io.py.
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  r70995 | benjamin.peterson | 2009-04-01 16:12:54 -0500 (Wed, 01 Apr 2009) | 1 line

  add seek constants to __all__
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