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