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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 user's private exchange Actually user's private channel needed to be defined only once, and this should be happened when user first created. But since this has a little performance cost, to be safe we always call it before binding to the channel we currently subscribe """

        channel = self._connect_mq()
        channel.exchange_declare(exchange=self.user.prv_exchange,
                                 exchange_type='fanout',
                                 durable=True)