```js
// create-event.js
// npm install ics

const { createEvent } = require(\"ics\");
const fs = require(\"fs\");

const event = {
  title: \"Birthday Party\",
  start: [2024, 7, 20], // YYYY, M, D
  duration: { hours: 2 },
  attendees: [
    { name: \"Alice\" },
    { name: \"Bob\" }
  ]
};

createEvent(event, (error, value) => {
  if (error) {
    console.error(\"Error creating event:\", error);
    return;
  }

  fs.writeFileSync(\"birthday-party.ics\", value);
  console.log(\"Calendar event created: birthday-party.ics\");
});
```

Run it with:

```bash
npm install ics
node create-event.js
```

This will generate a `birthday-party.ics` file you can import into a calendar app.