It looks like it was not included in this video. Here is a link to a previous video - https://www.youtube.com/watch?v=Q7EuXNw0DaA&list=PL240A9CB42552316A&t=190

It looks like it was not included in this video. Here is a link to a previous video - https://www.youtube.com/watch?v=Q7EuXNw0DaA&list=PL240A9CB42552316A&t=190s https://www.youtube.com/watch?v=Q7EuXNw0DaA&list=PL240A9CB42... I think it is better if he explains it