public function uniqueExceptItself($attribute, $params)
    {
        $_attribute = '_' . $attribute;
        $value = $this->$attribute;
        $_value = $this->$_attribute;
        if($value <> $_value) {
            $found = false;
            if(Rubric::find()->select([$attribute])->where([$attribute => $value])->count() > 0) {
                $this->addError($attribute, Module::t('core', '{attribute} "{value}" has already been taken.', [
                    'attribute' => ucfirst($attribute), 'value' => $value,
                ]));
            }
        }
    }