Working with collection in jasascript

const isAnObject = (item) => typeof item === 'object' && item !== null && !Array.isArray(item); const sortObjectKeys = (item) => { return Object.keys(item) .sort() .filter((key) => [null, undefined, ''].includes(item[key]) === false) .reduce((acc, key) => { acc[key] = isAnObject(item[key]) ? sortObjectKeys(item[key]) : item[key]; return acc; }, {}); }; const sortObjectsKeys = (items) => { return items.map((item) => { if (isAnObject(item)) { return sortObjectKeys(item); } return item; }); }; https.get( 'https://harry-potter-api-3a23c827ee69.herokuapp.com/api/characters', (res) => { let data = []; const headerDate = res.headers && res.headers.date ? res.headers.date : 'no response date'; console.log('Status Code:', res.statusCode); console.log('Date in Response header:', headerDate); res.on('data', (chunk) => { data.push(chunk); }); res.on('end', () => { console.log('Response ended:'); const users = JSON.parse(Buffer.concat(data).toString()); console.log('Response:', sortObjectsKeys(users.slice(0, 6))); }); } ).on('error', (err) => { console.log('Error: ', err.message); });