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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def pickle_dumps(self, protocol=None):
 """ Return a string with the pickle representation. `protocol` selects the pickle protocol. self.pickle_protocol is used if `protocol` is None """

        strio = StringIO()
        pmg_pickle_dump(self, strio,
                        protocol=self.pickle_protocol if protocol is None
                        else protocol)
        return strio.getvalue()