code: func SetOriginalConfiguration(info *resource.Info, original []byte) error {
  	if len(original) < 1 {
  		return nil
  	}
  
  	accessor := info.Mapping.MetadataAccessor
  	annotations, err := accessor.Annotations(info.Object)
  	if err != nil {
  		return err
  	}
  
  	if annotations == nil {
  		annotations = map[string]string{}
  	}
  
  	annotations[LastAppliedConfigAnnotation] = string(original)
  	if err := info.Mapping.MetadataAccessor.SetAnnotations(info.Object, annotations); err != nil {
  		return err
  	}
  
  	return nil
  }
docs: // SetOriginalConfiguration sets the original configuration of the object
  // as the annotation on the object for later use in computing a three way patch.