code: public CreateImageResponse createImageFromInstance(String imageName, String instanceId) {
          return createImage(new CreateImageRequest()
                  .withImageName(imageName).withInstanceId(instanceId));
      }
docs: Creating a customized image from the instance..
  
  <p>
  While creating an image from an instance,the instance must be Running or Stopped,
  otherwise,it's will get <code>409</code> errorCode.
  
  This is an asynchronous interface,
  you can get the latest status by invoke {@link #getImage(GetImageRequest)}
  
  @param imageName The name of image that will be created.
  @param instanceId The id of instance which will be used to create image.
  @return The response with id of image newly created.