docs: def support_jsonp(api_instance, callback_name_source='callback'):
      """Let API instance can respond jsonp request automatically.
  
      `callback_name_source` can be a string or a callback.
          If it is a string, the system will find the argument that named by this string in `query string`.
           If found, determine this request to be a jsonp request, and use the argument's value as the js callback name.
  
          If `callback_name_source` is a callback, this callback should return js callback name when request
           is a jsonp request, and return False when request is not jsonp request.
           And system will handle request according to its return value.
  
      default support format：url?callback=js_callback_name
      """
      output_json = api_instance.representations['application/json']
  
      @api_instance.representation('application/json')
      def handle_jsonp(data, code, headers=None):
          resp = output_json(data, code, headers)
  
          if code == 200:
              callback = request.args.get(callback_name_source, False) if not callable(callback_name_source) \
                  else callback_name_source()
              if callback:
                  resp.set_data(str(callback) + '(' + resp.get_data().decode("utf-8") + ')')
  
          return resp