code: public Observable<RegistryInner> createAsync(String resourceGroupName, String registryName, RegistryCreateParameters registryCreateParameters) {
          return createWithServiceResponseAsync(resourceGroupName, registryName, registryCreateParameters).map(new Func1<ServiceResponse<RegistryInner>, RegistryInner>() {
              @Override
              public RegistryInner call(ServiceResponse<RegistryInner> response) {
                  return response.body();
              }
          });
      }
docs: Creates a container registry with the specified parameters.
  
  @param resourceGroupName The name of the resource group to which the container registry belongs.
  @param registryName The name of the container registry.
  @param registryCreateParameters The parameters for creating a container registry.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable for the request