In your main file you used:

if event.type == pygame.K_SPACE:
    game.player.launch_projectile()

However, the "event.type" is just "pygame.KEYDOWN" and not "pygame.K_SPACE". You should use "game.pressed.get(pygame.K_SPACE)" instead:

if game.pressed.get(pygame.K_SPACE):
    game.player.launch_projectile()