docs: def stop_capture(self, cap_file_name=None, cap_file_format=IxeCapFileFormat.mem, *ports):
          """ Stop capture on ports.
  
          :param cap_file_name: prefix for the capture file name.
              Capture files for each port are saved as individual pcap file named 'prefix' + 'URI'.pcap.
          :param cap_file_format: exported file format
          :param ports: list of ports to stop traffic on, if empty stop all ports.
          :return: dictionary (port, nPackets)
          """
  
          port_list = self.set_ports_list(*ports)
          self.api.call_rc('ixStopCapture {}'.format(port_list))
  
          nPackets = {}
          for port in (ports if ports else self.ports.values()):
              nPackets[port] = port.capture.nPackets
              if nPackets[port]:
                  if cap_file_format is not IxeCapFileFormat.mem:
                      port.cap_file_name = cap_file_name + '-' + port.uri.replace(' ', '_') + '.' + cap_file_format.name
                      port.captureBuffer.export(port.cap_file_name)
          return nPackets