'Sprite groups created for convenience'

def setup_spritegroups(self):

    self.sprites_about_to_die_group = pg.sprite.Group()
    self.shell_group = pg.sprite.Group()
    self.enemy_group = pg.sprite.Group()
    self.ground_step_pipe_group = pg.sprite.Group(self.ground_group, self.pipe_group, self.step_group)
    self.mario_and_enemy_group = pg.sprite.Group(self.mario, self.enemy_group)
