How to use the realm.List function in realm

realm.write(() => {
            let obj = realm.create('PersonList', {list: []});
            TestCase.assertInstanceOf(obj.list, Realm.List);
            TestCase.assertInstanceOf(obj.list, Realm.Collection);
        });

        TestCase.assertThrowsContaining(() => new Realm.List(), 'constructor');
        TestCase.assertInstanceOf(Realm.List, Function);

function isRealmList(x) {
    return x !== null && x !== undefined && x.constructor === Realm.List
}