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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 ack(messageid, transactionid=None):
 """STOMP acknowledge command. Acknowledge receipt of a specific message from the server. messageid: This is the id of the message we are acknowledging, what else could it be? ;) transactionid: This is the id that all actions in this transaction will have. If this is not given then a random UUID will be generated for this. """

    header = 'message-id: %s' % messageid

    if transactionid:
        header = 'message-id: %s\ntransaction: %s' % (messageid, transactionid)

    return "ACK\n%s\n\n\x00\n" % header