code: def validate_payload_len(self, payload):
          
          if not hasattr(self, "PAYLOAD_LEN"):
              # No fixed payload len, e.g. within FrameGetSceneListNotification
              return
          # pylint: disable=no-member
          if len(payload) != self.PAYLOAD_LEN:
              raise PyVLXException("Invalid payload len", expected_len=self.PAYLOAD_LEN, current_len=len(payload), frame_type=type(self).__name__)
docs: Validate payload len.