docs: function ThrottledEvents(opts) {
    if (this instanceof ThrottledEvents) {
      this.opts = opts || {
        throttle: defaultThrottle
      };
      this.throttle = this.opts.throttle || defaultThrottle;
      this.p = Promise.resolve();
      this.size = 0;
      AsyncEvents.call(this);
    } else {
      return new ThrottledEvents(opts);
    }
  }