Contra was one of the earliest video games that allowed you to put in a cheat code... the game was so hard (at least to me) that you had to cheat. I remember playing the first Mario Brothers, they only gave you three lives and no ability to save. Kids (and grown-ups) today can save their progress as they succeed throughout a game... if you get killed off you simply start over again on your last save.
Anyway, it's kind of scary that someone took the time to nit a sweater like this.
Oh, the cheat code was: up, up, down, down, left, right, left, right, B, A, Start.