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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_packet_groups(self, clear_time_stamps=True, *ports):
 """ Start packet groups on ports. :param clear_time_stamps: True - clear time stamps, False - don't. :param ports: list of ports to start traffic on, if empty start on all ports. """

        port_list = self.set_ports_list(*ports)
        if clear_time_stamps:
            self.api.call_rc('ixClearTimeStamp {}'.format(port_list))
        self.api.call_rc('ixStartPacketGroups {}'.format(port_list))