Webos TV device Id and device model

I am trying to get webos tv device Id and model name, followed the documentation but I am getting webos is not defined error.
Downloaded webostv libraray placed inside src folder
In index.html added script tag

method: ‘getSystemInfo’,
parameters: {
keys: [‘modelName’, ‘firmwareVersion’, ‘UHD’, ‘sdkVersion’],
onComplete: function (inResponse) {
let isSucceeded = inResponse.returnValue;
if (isSucceeded) {
console.log('Result: ’ + JSON.stringify(inResponse));
const response = JSON.stringify(inResponse)
} else {
console.log(‘Failed to get TV device information’);

Please refer to Luna Service sample app. This app shows how to call luna service APIs using the service.request method in webOSTV.js library and is working without issues. Thank you.