code: def start_traffic(self, blocking=False, *ports):
          
  
          for chassis, chassis_ports in self._per_chassis_ports(*self._get_operation_ports(*ports)).items():
              chassis.start_traffic(False, *chassis_ports)
          if blocking:
              for chassis, chassis_ports in self._per_chassis_ports(*self._get_operation_ports(*ports)).items():
                  chassis.wait_traffic(*chassis_ports)
docs: Start traffic on list of ports.
  
          :param blocking: True - start traffic and wait until traffic ends, False - start traffic and return.
          :param ports: list of ports to start traffic on. Default - all session ports.