how to use the fromeventpattern function from the rxjs library in javascript

index.tsx
const { fromEventPattern } = require('rxjs');

// create an object with `addListener` and `removeListener` methods
const emitter = {
  addListener: (eventName, handler) => {
    document.addEventListener(eventName, handler);
  },
  removeListener: (eventName, handler) => {
    document.removeEventListener(eventName, handler);
  }
};

// create an Observable that listens for `'mousemove'` events
const mouseMove$ = fromEventPattern(
  handler => emitter.addListener('mousemove', handler),
  handler => emitter.removeListener('mousemove', handler)
);

// subscribe to the `mouseMove$` Observable to start listening for events
mouseMove$.subscribe(event => console.log(`Mouse event: ${event}`));
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