How to use the datx/dist/helpers/utils.mapItems function in datx

refs.forEach((ref: string) => {
        const items = (obj.relationships as IDictionary)[ref].data;
        if (items instanceof Array && items.length < 1) {
          // it's only possible to update items with one ore more refs. Early exit
          return;
        }
        if (items && record) {
          const models: Model|Array|IIdentifier|undefined|null = mapItems(
            items,
            (def: IDefinition) => this.find(def.type, def.id) || def.id,
          );

          const itemType: string = items instanceof Array ? items[0].type : items.type;
          if (ref in record) {
            record[ref] = models;
          } else {
            // @ts-ignore - Ignore until datx is updated
            initModelRef(record, ref, {model: itemType, type: ReferenceType.TO_ONE_OR_MANY}, models);
          }
        }
      });
    }

private __iterateEntries(body: IResponse, fn: (item: Model) => Model) {
      mapItems((body && body.included) || [], fn);
      return mapItems((body && body.data) || [], fn);
    }

private __iterateEntries(body: IResponse, fn: (item: Model) => Model) {
      mapItems((body && body.included) || [], fn);
      return mapItems((body && body.data) || [], fn);
    }