@Override
 protected CompletableFuture<Integer> getValue() {
   return lightbulb.getBrightness();
 }
 @Override
 public void unsubscribe() {
   lightbulb.unsubscribeBrightness();
 }
 @Override
 protected void setValue(Integer value) throws Exception {
   lightbulb.setBrightness(value);
 }
 @Override
 public void subscribe(HomekitCharacteristicChangeCallback callback) {
   lightbulb.subscribeBrightness(callback);
 }