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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 stop_transmit(self, *ports):
 """ Stop traffic on ports. :param ports: list of ports to stop traffic on, if empty start on all ports. """


        port_list = self.set_ports_list(*ports)
        self.api.call_rc('ixStopTransmit {}'.format(port_list))
        time.sleep(0.2)