docs: public Observable<SignalRKeysInner> beginRegenerateKeyAsync(String resourceGroupName, String resourceName) {
          return beginRegenerateKeyWithServiceResponseAsync(resourceGroupName, resourceName).map(new Func1<ServiceResponse<SignalRKeysInner>, SignalRKeysInner>() {
              @Override
              public SignalRKeysInner call(ServiceResponse<SignalRKeysInner> response) {
                  return response.body();
              }
          });
      }