checks if something is 4.
// CommonJS
const is4 = require('is-4');
console.log(is4(4)); // true
console.log(is4('4')); // false
console.log(is4(5)); // false// ESM
import is4 from 'is-4';
console.log(is4(4)); // true
console.log(is4('4')); // false
console.log(is4(5)); // false