Blocked revisions 66043 via svnmerge

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  r66043 | antoine.pitrou | 2008-08-27 00:42:08 +0200 (mer., 27 août 2008) | 11 lines

  Issue #2534: speed up isinstance() and issubclass() by 50-70%, so as to
  match Python 2.5 speed despite the __instancecheck__ / __subclasscheck__
  mechanism. In the process, fix a bug where isinstance() and issubclass(),
  when given a tuple of classes as second argument, were looking up
  __instancecheck__ / __subclasscheck__ on the tuple rather than on each
  type object.

  Reviewed by Benjamin Peterson and Raymond Hettinger.
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