code: def _append_comment(ret, comment):
      '''
      append ``comment`` to ``ret['comment']``
      '''
      if ret['comment']:
          ret['comment'] = ret['comment'].rstrip() + '\n' + comment
      else:
          ret['comment'] = comment
  
      return ref _append_comment(ret, comment):
      '''
      append ``comment`` to ``ret['comment']``
      '''
      if ret['comment']:
          ret['comment'] = ret['comment'].rstrip() + '\n' + comment
      else:
          ret['comment'] = comment
  
      return ret
docs: append ``comment`` to ``ret['comment']``