code: func (m *kubeGenericRuntimeManager) getImageUser(image string) (*int64, string, error) {
  	imageStatus, err := m.imageService.ImageStatus(&runtimeapi.ImageSpec{Image: image})
  	if err != nil {
  		return nil, "", err
  	}
  
  	if imageStatus != nil {
  		if imageStatus.Uid != nil {
  			return &imageStatus.GetUid().Value, "", nil
  		}
  
  		if imageStatus.Username != "" {
  			return nil, imageStatus.Username, nil
  		}
  	}
  
  	// If non of them is set, treat it as root.
  	return new(int64), "", nil
  }
docs: // getImageUser gets uid or user name that will run the command(s) from image. The function
  // guarantees that only one of them is set.