code: function getMatchingAsids (id, id_type) {
    return new Promise (async (resolve, reject) => {
      try {
        let response = await this.callIdMatchingApi(id, id_type, 'asid');
        resolve(response);
      } catch (e) {
        reject(e);
      }
    });
  }
docs: Returns all app-scoped IDs (ASIDs) for a user across all Pages in the same
  Facebook Business Manager account. Matches can be found using
  a PSID or ASID. Uses the [ID Matching API](https://developers.facebook.com/docs/messenger-platform/identity/id-matching).
  @param  {String} id        A valid ASID or PSID.
  @param  {String} id_type   The type of ID provided in the `id` argument: `ASID` or `PSID`.
  @return {Promise<Object>}  The API response
  @memberof  Client#
  @example
  Client.getMatchingAsids('95740976304764', 'PSID')
  .then(res => {
  console.log(res);
  // {
  //    "data": [
  //      {
  //        "id": "7234541381429384",
  //        "app": {
  //            "link": "https://www.facebook.com/games/?app_id=299493827472589",
  //            "name": "MyApp1",
  //            "id": "9948573218738365"
  //        }
  //      },
  //      {
  //        "id": "9384723459125445",
  //        "app": {
  //            "link": "https://www.facebook.com/games/?app_id=299490394856589",
  //            "name": "MyApp2",
  //            "id": "689384785732187"
  //        }
  //      }
  //    ],
  //    "paging": {
  //        "cursors": {
  //            "before": "ODczODM2NQZDZDMTA4MDYxNjQ2",
  //            "after": "TcxOTQzMTY1NjgyNDk4M"
  //        }
  //    }
  // }
  });