const {Worker, isMainThread, parentPort, workerData} = require('worker_threads');
if (isMainThread) {
 const worker = new Worker(__filename, {workerData: {num: 5}});
 worker.once('message', (result) => {
 console.log('square of 5 is :', result);
 })
} else {
 parentPort.postMessage(workerData.num * workerData.num)
}