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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 basic_ack(self, delivery_tag, multiple=False):
 """Acknowledge one or more messages This method acknowledges one or more messages delivered via the Deliver or Get-Ok methods. The client can ask to confirm a single message or a set of messages up to and including a specific message. PARAMETERS: delivery_tag: longlong server-assigned delivery tag The server-assigned and channel-specific delivery tag RULE: The delivery tag is valid only within the channel from which the message was received. I.e. a client MUST NOT receive a message on one channel and then acknowledge it on another. RULE: The server MUST NOT use a zero value for delivery tags. Zero is reserved for client use, meaning "all messages so far received". multiple: boolean acknowledge multiple messages If set to True, the delivery tag is treated as "up to and including", so that the client can acknowledge multiple messages with a single method. If set to False, the delivery tag refers to a single message. If the multiple field is True, and the delivery tag is zero, tells the server to acknowledge all outstanding mesages. RULE: The server MUST validate that a non-zero delivery- tag refers to an delivered message, and raise a channel exception if this is not the case. """

        args = AMQPWriter()
        args.write_longlong(delivery_tag)
        args.write_bit(multiple)
        self._send_method((60, 80), args)