code: def unflag_message(current):
      
      current.output = {'status': 'OK', 'code': 200}
  
      FlaggedMessage(current).objects.filter(user_id=current.user_id,
                                             message_id=current.input['key']).delete()
docs: remove flag of a message
  
      .. code-block:: python
  
          # request:
          {
              'view':'_zops_flag_message',
              'key': key,
          }
          # response:
              {
              '
              'status': 'OK',
              'code': 200,
              }