code: func (c *Commit_TreeDiff_ChangeType) UnmarshalJSON(data []byte) error {
  	var s string
  	if err := json.Unmarshal(data, &s); err != nil {
  		return err
  	}
  
  	change, ok := Commit_TreeDiff_ChangeType_value[strings.ToUpper(s)]
  	if !ok {
  		return fmt.Errorf("unexpected change type %q", s)
  	}
  
  	*c = Commit_TreeDiff_ChangeType(change)
  	return nil
  }
docs: // UnmarshalJSON parses a string representation of the change.