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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 recover(self, requeue=False):
 """Redeliver unacknowledged messages. :param bool requeue: Re-queue the messages :raises AMQPInvalidArgument: Invalid Parameters :raises AMQPChannelError: Raises if the channel encountered an error. :raises AMQPConnectionError: Raises if the connection encountered an error. :rtype: dict """

        if not isinstance(requeue, bool):
            raise AMQPInvalidArgument('requeue should be a boolean')
        recover_frame = specification.Basic.Recover(requeue=requeue)
        return self._channel.rpc_request(recover_frame)