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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 log_proto(self, proto, step_num):
 """Log a Summary protobuf to the event file. :param proto: a Summary protobuf :param step_num: the iteration number at which this value was logged """

        self.summ_writer.add_summary(proto, step_num)
        return proto