docs: public Observable<VirtualMachineScaleSetInner> beginUpdateAsync(String resourceGroupName, String vmScaleSetName, VirtualMachineScaleSetUpdate parameters) {
          return beginUpdateWithServiceResponseAsync(resourceGroupName, vmScaleSetName, parameters).map(new Func1<ServiceResponse<VirtualMachineScaleSetInner>, VirtualMachineScaleSetInner>() {
              @Override
              public VirtualMachineScaleSetInner call(ServiceResponse<VirtualMachineScaleSetInner> response) {
                  return response.body();
              }
          });
      }