code: def get_payload(self):
          
          ret = bytes([self.session_id >> 8 & 255, self.session_id & 255])
          ret += bytes([self.originator.value])
          ret += bytes([self.priority.value])
          ret += bytes([self.scene_id])
          ret += bytes([self.velocity.value])
          return ret
docs: Return Payload.