code: public Observable<Page<TopLevelDomainInner>> listAsync() {
          return listWithServiceResponseAsync()
              .map(new Func1<ServiceResponse<Page<TopLevelDomainInner>>, Page<TopLevelDomainInner>>() {
                  @Override
                  public Page<TopLevelDomainInner> call(ServiceResponse<Page<TopLevelDomainInner>> response) {
                      return response.body();
                  }
              });
      }
docs: Get all top-level domains supported for registration.
  Get all top-level domains supported for registration.
  
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable to the PagedList&lt;TopLevelDomainInner&gt; object