private function getOperators()
    {
        return [
            Operator::$wildcard,
            Operator::$equals,
            Operator::$doesNotEqual,
            Operator::$greaterThanOrEqual,
            Operator::$lessThanOrEqual,
            Operator::$approximateEqual,
            Operator::$startsWith,
            Operator::$endsWith,
            Operator::$contains,
            Operator::$and,
        ];
    }