svn+ssh://pythondev@svn.python.org/python/branches/py3k

........
  r84301 | daniel.stutzbach | 2010-08-24 15:49:57 -0500 (Tue, 24 Aug 2010) | 1 line

  Issue 8750: Fixed MutableSet's methods to correctly handle reflexive operations, namely x -= x and x ^= x
........