JavaScript Dict/Object Map

let items = {    1: 'One',    2: 'Two',    3: 'Three'}

Object.keys(items).map((key, index) => {    items[key] = `${items[key]} is ${key}`})// orfor (key in items) {    items[key] = `${items[key]} is ${key}`}console.log(items) // {1: "One is 1", 2: "Two is 2", 3: "Three is 3"}

const newItems = Object.keys(items).reduce((result, key) => {    result[key] = `${items[key]} is ${key}`    return result}, {})