code: function getBoundSuper(obj, fn) {
    if (typeof _WeakMap === 'undefined') {
      throw new Error('Using @autobind on ' + fn.name + '() requires WeakMap support due to its use of super.' + fn.name + '()');
    }
  
    if (!mapStore) {
      mapStore = new _WeakMap();
    }
  
    if (mapStore.has(obj) === false) {
      mapStore.set(obj, new _WeakMap());
    }
  
    var superStore = mapStore.get(obj);
    // $FlowFixMe: already insure superStore is not undefined
    if (superStore.has(fn) === false) {
      // $FlowFixMe: already insure superStore is not undefined
      superStore.set(fn, bind$1(fn, obj));
    }
    // $FlowFixMe: already insure superStore is not undefined
    return superStore.get(fn);
  }
docs: save bound function for super