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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 _start_separate_timer(self, transaction):
 """ Start a thread to handle separate mode. :type transaction: Transaction :param transaction: the transaction that is in processing :rtype : the Timer object """

        t = threading.Timer(defines.ACK_TIMEOUT, self._send_ack, (transaction,))
        t.start()
        return t