Merged revisions 78274 via svnmerge from

Merged revisions 78274 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk

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  r78274 | r.david.murray | 2010-02-20 23:23:00 -0500 (Sat, 20 Feb 2010) | 9 lines

  Issue 7970: When email.Parser.Parser parses a MIME message of type
  message/rfc822 it turns it into an object whose body consists of
  a list containing a single Message object.  HeaderParser, on the
  other hand, just copies the body as a string.  Generator.flatten
  has a special handler for the message mime type that expected the
  body to be the one item list.  This fails if the message was parsed
  by HeaderParser.  So we now check to see if the body is a string
  first, and if so just we just emit it.
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