Stream Writable Lab

In this lab, you will learn how to work with stream.Writable in Node.js by implementing a writable stream that logs the data it receives. stream.Writable is an abstract class and you have to implement two methods: _write and _final. _write will be called with the data that the stream is receiving, and _final will be called when the stream is ended. Implement these two methods and create a writable stream instance. Then, test your implementation by writing some data to it and ending the stream.

Concepts you will learn:

1. How to create a custom writable stream
2. Using the _write method
3. Using the _final method