How to use the flatpickr/package.json.version function in flatpickr

angularRouter: require('@angular/router/package.json').version,
  angularCalendar: require('../../../package.json').version,
  calendarUtils: require('calendar-utils/package.json').version,
  angularResizableElement: require('angular-resizable-element/package.json')
    .version,
  angularDraggableDroppable: require('angular-draggable-droppable/package.json')
    .version,
  dateFns: require('date-fns/package.json').version,
  rxjs: require('rxjs/package.json').version,
  bootstrap: require('bootstrap-css-only/package.json').version,
  zoneJs: require('zone.js/package.json').version,
  ngBootstrap: require('@ng-bootstrap/ng-bootstrap/package.json').version,
  rrule: require('rrule/package.json').version,
  fontAwesome: require('font-awesome/package.json').version,
  positioning: require('positioning/package.json').version,
  flatpickr: require('flatpickr/package.json').version,
  angularxFlatpickr: require('angularx-flatpickr/package.json').version
};

@Component({
  selector: 'mwl-demo-app',
  styleUrls: ['./demo-app.css'],
  templateUrl: './demo-app.html'
})
export class DemoAppComponent implements OnInit {
  demos: Demo[] = [];
  filteredDemos: Demo[] = [];
  activeDemo: Demo;
  isMenuVisible = false;
  firstDemoLoaded = false;
  searchText = '';
  copied$ = new Subject();