JSFiddle - React, Tailwind, and code Playground

JavaScript

var obj = {
   1: 'a',
   2: 'b'
};

function* entries(obj) {
  for (let key of Object.keys(obj)) {
    yield [key, obj[key]];
  }
}

let generator = entries(obj);

let step1 = generator.next();
let step2 = generator.next();
let step3 = generator.next();

console.log(JSON.stringify(step1));
console.log(JSON.stringify(step2));
console.log(JSON.stringify(step3));