code: public Observable<LuisApp> exportAsync(UUID appId, String versionId) {
          return exportWithServiceResponseAsync(appId, versionId).map(new Func1<ServiceResponse<LuisApp>, LuisApp>() {
              @Override
              public LuisApp call(ServiceResponse<LuisApp> response) {
                  return response.body();
              }
          });
      }
docs: Exports a LUIS application to JSON format.
  
  @param appId The application ID.
  @param versionId The version ID.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable to the LuisApp object