makes a clone copy of the mapper. It won't clone the serializers or deserializers and it won't copy the events

def copy(self):
        '''
         makes a clone copy of the mapper. It won't clone the serializers or deserializers and it won't copy the events
        '''
        try:
            tmp = self.__class__()
        except Exception:
            tmp = self.__class__(self._pdict)
            
        tmp._serializers = self._serializers
        tmp.__deserializers = self.__deserializers

        return tmp