def previous_rev(self, rev, path=''):
        # FIXME optimize for non-scoped
        rev = self.normalize_rev(rev)
        return self._previous_rev(rev, path)
>>> opp('x'), opp('o')
dataset/ETHPy150Open edgewall/trac/tracopt/versioncontrol/svn/svn_fs.py/SubversionRepository.previous_rev--crossover with--dataset/ETHPy150Open thomasballinger/curtsies/examples/tictactoeexample.py/opp