bubasuma\simplechat\models\User::findIdentity PHP Method

    public static function findIdentity($id)
    {
        return static::findOne(['id' => $id]);
    }

 /**
  * @return User
  */
 public function getUser()
 {
     if (null === $this->_user) {
         $this->_user = User::findIdentity(\Yii::$app->session->get($this->module->id . '_user', 1));
     }
     return $this->_user;
 }