code: def set_mode(self, mode, custom_mode = 0, custom_sub_mode = 0):
          '''set arbitrary flight mode'''
          mav_autopilot = self.field('HEARTBEAT', 'autopilot', None)
          if mav_autopilot == mavlink.MAV_AUTOPILOT_PX4:
              self.set_mode_px4(mode, custom_mode, custom_sub_mode)
          else:
              self.set_mode_apm(modef set_mode(self, mode, custom_mode = 0, custom_sub_mode = 0):
          '''set arbitrary flight mode'''
          mav_autopilot = self.field('HEARTBEAT', 'autopilot', None)
          if mav_autopilot == mavlink.MAV_AUTOPILOT_PX4:
              self.set_mode_px4(mode, custom_mode, custom_sub_mode)
          else:
              self.set_mode_apm(mode)
docs: set arbitrary flight mode