Space Survival PuDou the survivor - python made game

I've decided to make a suvival, shooting, dodge, space game with python. The most important part is to learn more about python, different functions. I've learnt about how an object rotate according to the mouse via object x/y location, using various mathematical functions (atan2, sin, cos) for bullet movement according to rotation.

Also learnt about how to draw circles, ellipse, set up pygame.USEREVENT (for activities timing), pygame objects' alpha set up, animation, played alot with alpha value, and functions from 'random' library.