code: def complete_serial_ports(self, text):
          '''return list of serial ports'''
          ports = mavutil.auto_detect_serial(preferred_list=preferred_ports)
          return [ p.device for p in ports f complete_serial_ports(self, text):
          '''return list of serial ports'''
          ports = mavutil.auto_detect_serial(preferred_list=preferred_ports)
          return [ p.device for p in ports ]
docs: return list of serial ports