code: def start(self):
          
          global CODE
          url = self._get_auth_url()
          webbrowser.open(url)
          tornado.ioloop.IOLoop.current().start()
          self.code = CODE
docs: Starts the `PrawOAuth2Server` server. It will open the default
          web browser and it will take you to Reddit's authorization page,
          asking you to authorize your Reddit account(or account of the bot's)
          with your app(or bot script). Once authorized successfully, it will
          show `successful` message in web browser.