It's python but In these series of tutorials you don't need to learn the language first, You'll learn how to make your first game and on the side you'll learn enough of python whenever you need to.
However, you need to follow the series for that, on top of each part there is a link to the previous part you can follow all the way to the first one. and another link on bottom of each part leading to the next.
I suggest starting from the beginning