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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 shutdown(self):
 """Start the connection shutdown process, cancelling any active consuming and closing the channel if the connection is not active. """

        if self.is_shutting_down:
            self.logger.debug('Already shutting down')
            return

        self.set_state(self.STATE_SHUTTING_DOWN)
        self.logger.debug('Shutting down connection')
        if not self.is_active:
            return self.channel.close()
        self.logger.debug('Sending a Basic.Cancel to RabbitMQ')
        self.channel.basic_cancel(self.on_consumer_cancelled,
                                  self.consumer_tag)