Udemy cheating for free

Do you know udemy.com? A big online learning website, which had a lot of courses. Some courses are charged with high cost you can not afford.

I'm learning AWS SA, i did not find any useful and free stuff on internet. So i come to Udemy, register one account, and pay one course with  $199. 

To me, it's so a big number. I dive into that course with high priority. But one day, i want to watch all the course's video offline because of the fcking low network.

I found udemy-dl, which can download all video of mine. Suddenly, the lighting come across my mind, i think i could do something more than udemy-dl can do.

It take 2 day to rewrite udemy-dl to my own udemy-dl. Now, i can download any course from Udemy without charging fee.
You can reference my code here