Merged revisions 79522 via svnmerge from

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

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  r79522 | ezio.melotti | 2010-03-31 10:26:24 +0300 (Wed, 31 Mar 2010) | 1 line

  Revert r79179 and merge r75584 to explain how to implement a queue using collection.deque instead of a list.
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