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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 rpc_reply(self, body, properties=None, exchange=None, reply_to=None, connection=None):
 """Reply to the message that is currently being processed. .. versionadded:: 4.0.0 If the exchange is not specified, the exchange of the message that is currently being processed by the Consumer will be used. If ``reply_to`` is not provided, it will attempt to use the ``reply_to`` property of the message that is currently being processed by the consumer. If both are not set, a :exc:`ValueError` is raised. If any of the following message properties are not provided, they will automatically be assigned: - ``app_id`` - ``correlation_id`` - ``message_id`` - ``timestamp`` The ``correlation_id`` will only be automatically assigned if the original message provided a ``message_id``. If the connection that the message is being published on has publisher confirmations enabled, a :py:class:`~tornado.concurrent.Future` is returned. :param body: The message body :type body: :class:`bytes` or :class:`str` :param properties: The AMQP properties to use for the reply message :type properties: :class:`dict` or :data:`None` :param exchange: The exchange to publish to. Defaults to the exchange of the message that is currently being processed by the Consumer. :type exchange: :class:`str` or :data:`None` :param reply_to: The routing key to send the reply to. Defaults to the reply_to property of the message that is currently being processed by the Consumer. If neither are set, a :exc:`ValueError` is raised. :type reply_to: class:`str` or :data:`None` :param connection: The connection to use. If it is not specified, the channel that the message was delivered on is used. :type connection: :class:`str` :rtype: :class:`tornado.concurrent.Future` or :data:`None` :raises: :exc:`ValueError` """

        if reply_to is None and self.reply_to is None:
            raise ValueError('Missing reply_to routing key')
        properties = properties or {}
        if not properties.get('app_id'):
            properties['app_id'] = self.name
        if not properties.get('correlation_id') and self.message_id:
            properties['correlation_id'] = self.message_id
        if not properties.get('message_id'):
            properties['message_id'] = str(uuid.uuid4())
        if not properties.get('timestamp'):
            properties['timestamp'] = int(time.time())
        return self.publish_message(exchange or self.exchange, reply_to
                                    or self.reply_to, properties, body,
                                    connection)