Returns the key with highest numerical value. Returns an array of keys if two or more keys have the same numerical value.
function keyWithLargestValue<T extends object>(obj: T)
// Example:
keyWithLargestValue({ a: 1, b: 2, c: 3 }) //=> "c"
keyWithLargestValue({ a: 1, b: 3, c: 3 }) //=> ["b", "c"]