How to use the @storybook/core-events.REGISTER_SUBSCRIPTION function in @storybook/core-events

const applyViewportOptions = (options = {}) => {
  const channel = addons.getChannel();

  handler = options.onViewportChange || noop;
  if (options.onViewportChange) {
    channel.emit(CoreEvents.REGISTER_SUBSCRIPTION, subscription);
  }

  channel.emit(SET_STORY_DEFAULT_VIEWPORT_EVENT_ID, options.name || DEFAULT_VIEWPORT);
};

const addEvents = ({ emit, events }) => {
  if (prevEvents !== events) {
    addons.getChannel().emit(EVENTS.ADD, events);
    prevEvents = events;
  }
  currentEmit = emit;
  addons.getChannel().emit(CoreEvents.REGISTER_SUBSCRIPTION, subscription);
};

const metaSubscription = () => {
  addons.getChannel().on(Events.REGISTER_SUBSCRIPTION, subscriptionsStore.register);
  return () =>
    addons.getChannel().removeListener(Events.REGISTER_SUBSCRIPTION, subscriptionsStore.register);
};

const metaSubscription = () => {
  addons.getChannel().on(Events.REGISTER_SUBSCRIPTION, metaSubscriptionHandler);
  return () =>
    addons.getChannel().removeListener(Events.REGISTER_SUBSCRIPTION, metaSubscriptionHandler);
};

return () =>
    addons.getChannel().removeListener(Events.REGISTER_SUBSCRIPTION, metaSubscriptionHandler);
};

return () =>
    addons.getChannel().removeListener(Events.REGISTER_SUBSCRIPTION, subscriptionsStore.register);
};

return () =>
    addons.getChannel().removeListener(Events.REGISTER_SUBSCRIPTION, subscriptionsStore.register);
};

const metaSubscription = () => {
  addons.getChannel().on(Events.REGISTER_SUBSCRIPTION, subscriptionsStore.register);
  return () =>
    addons.getChannel().removeListener(Events.REGISTER_SUBSCRIPTION, subscriptionsStore.register);
};