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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 declare_queue(self, queue_name):
 """Declare a queue. Has no effect if a queue with the given name already exists. Parameters: queue_name(str):
 The name of the new queue. Raises: ConnectionClosed: If the underlying channel or connection has been closed. """

        attempts = 1
        while True:
            try:
                if queue_name not in self.queues:
                    self.emit_before("declare_queue", queue_name)
                    self._declare_queue(queue_name)
                    self.queues.add(queue_name)
                    self.emit_after("declare_queue", queue_name)

                    delayed_name = dq_name(queue_name)
                    self._declare_dq_queue(queue_name)
                    self.delay_queues.add(delayed_name)
                    self.emit_after("declare_delay_queue", delayed_name)

                    self._declare_xq_queue(queue_name)
                break
            except (pika.exceptions.AMQPConnectionError,
                    pika.exceptions.AMQPChannelError) as e:  # pragma: no cover
                # Delete the channel and the connection so that the next
                # caller may initiate new ones of each.
                del self.channel
                del self.connection

                attempts += 1
                if attempts > MAX_DECLARE_ATTEMPTS:
                    raise ConnectionClosed(e) from None

                self.logger.debug(
                    "Retrying declare due to closed connection. [%d/%d]",
                    attempts, MAX_DECLARE_ATTEMPTS,
                )