code: func (f *File) Normalize() error {
  	me := errors.MultiError(nil)
  	for tname, t := range f.Template {
  		if err := t.Normalize(); err != nil {
  			me = append(me, fmt.Errorf("for template %q: %s", tname, err))
  		}
  	}
  	if len(me) > 0 {
  		return me
  	}
  	return nil
  }
docs: // Normalize will normalize all of the Templates in this message, returning an
  // error if any are invalid.