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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 create_exchange(self):
 """ Creates MQ exchange for this channel Needs to be defined only once. """

        mq_channel = self._connect_mq()
        mq_channel.exchange_declare(exchange=self.code_name,
                                    exchange_type='fanout',
                                    durable=True)