In Javascript please

Write a function `keyValueDuplicates(obj)` that takes an object as

an argument and returns an array containing all keys that are also

values in that object.

Examples:

obj1 = { orange: "juice", apple: "sauce", sauce: "pan" };

console.log(keyValueDuplicates(obj1)); // ["sauce"]

obj2 = { big: "foot", foot: "ball", ball: "boy", boy: "scout" };

console.log(keyValueDuplicates(obj2)); // ["foot", "ball", "boy"]

obj3 = { pizza: "pie", apple: "pie", pumpkin: "pie" };

console.log(keyValueDuplicates(obj3)); // []