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const map1 = new Map();
map1.set('bar', 'foo');
console.log(map1.has('bar'));
// Expected output: true
console.log(map1.has('baz'));
// Expected output: false
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const set1 = new Set([1, 2, 3]);
let map1 = new Map();
map1.set('info', {name: 'Jack', age: "26"});
// check if an element is in Set
console.log(map1.has('info')); // true