Method __reduce_ex__

Lib/test/pickletester.py:4290–4292

(self, proto)

    """Calling base class method should succeed"""
    _proto = None
    def __reduce_ex__(self, proto):
        self._proto = proto
        return object.__reduce_ex__(self, proto)

class REX_five(object):
    """This one used to fail with infinite recursion"""