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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 stop(self, signum=None, _unused=None):
 """Stop the consumer from consuming by calling BasicCancel and setting our state. :param int signum: The signal received :param frame _unused: The stack frame from when the signal was called """

        LOGGER.debug('Stop called in state: %s', self.state_description)
        if self.is_stopped:
            LOGGER.warning('Stop requested but consumer is already stopped')
            return
        elif self.is_shutting_down:
            LOGGER.warning('Stop requested, consumer is already shutting down')
            return
        elif self.is_waiting_to_shutdown:
            LOGGER.warning('Stop requested but already waiting to shut down')
            return

        # Stop consuming and close AMQP connections
        self.shutdown_connections()

        # Wait until the consumer has finished processing to shutdown
        if self.is_processing:
            LOGGER.info('Waiting for consumer to finish processing')
            self.set_state(self.STATE_STOP_REQUESTED)
            if signum == signal.SIGTERM:
                signal.siginterrupt(signal.SIGTERM, False)
            return