const f1 = () => {
  const obj1 = { a: 1, b: 2 }
  const obj2 = { a: 2, c: 3, d: 4}
	
 	let obj3 = null;
  // code here
  
  console.log(obj3) // It should be { a:1, b:2, c3, d:4}
  console.log(obj3) // It should be { a:2, b:2, c3, d:4}
}

f1();