medium-9.js

class Base {
    foo() {return 'foo in Base';}
    static bar() {return 'bar in Base';}
}
class Child extends Base {
    foo() {return super.foo();}
    static bar() {return super.bar();}
}

const obj = new Child;
console.log(obj.foo()); // foo in Base
console.log(Child.bar()); // bar in Base