const james = {
    name: 'James',
    height: `5'10"`,
    weight: 185,
    [Symbol.iterator]: function() {
        const object = this;
        const keys = Object.keys(object);
        let index = 0;
        
        return { 
            next: () => {
                const key = keys[index];
                index++;
                return { value: object[key], key: key, done: !(index < keys.length) };
            }
        };
    }
};

let iterator = james[Symbol.iterator]();

console.log(iterator.next().value); // 'James'
console.log(iterator.next().value); // `5'10`
console.log(iterator.next().value); // 185