code: public Observable<List<PrebuiltDomain>> listAvailableCustomPrebuiltDomainsForCultureAsync(String culture) {
          return listAvailableCustomPrebuiltDomainsForCultureWithServiceResponseAsync(culture).map(new Func1<ServiceResponse<List<PrebuiltDomain>>, List<PrebuiltDomain>>() {
              @Override
              public List<PrebuiltDomain> call(ServiceResponse<List<PrebuiltDomain>> response) {
                  return response.body();
              }
          });
      }
docs: Gets all the available custom prebuilt domains for a specific culture.
  
  @param culture Culture.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable to the List&lt;PrebuiltDomain&gt; object