code: function login(options) {
    if (!gui.isActive()) {
      throw new Error('Cannot login without a GUI.');
    }
  
    if (!options.scope) {
      throw new Error('Must specify list of requested scopes');
    }
    var params = {
      response_type: 'token',
      client_id: core.clientId,
      redirect_uri: 'https://api.twitch.tv/kraken/',
      scope: options.scope.join(' '),
    };
  
    if(options.force_verify) {
      params.force_verify = true;
    }
  
    if (!params.client_id) {
      throw new Error('You must call init() before login()');
    }
  
    gui.popupLogin(params);
  }
docs: Opens a login popup for Twitch if the SDK was initialized with a GUI and
  the user is not logged in yet.
  @method login
  @param {Object} options
  @example
  ```javascript
  Twitch.login({
  scope: ['user_read', 'channel_read']
  });
  ```