ngx-translate load from object map, key/value

gistfile1.txt

import { Observable } from 'rxjs/Observable';

const translations: any = {
  'stage_headline' : 'hello'
};

class MappedDataLoader implements TranslateLoader {
  getTranslation(lang: string): Observable<any> {
    return Observable.of(translations);
  }
}

  TranslateModule.forRoot({
                loader: {
                    provide: TranslateLoader,
                    useClass: MappedDataLoader
                }
            })