registry = []


def register(func):
    print('running register(%s)' % func)
    registry.append(func.__name__)
    return func


@register
def f1():
    print("running f1()")


@register
def f2():
    print("running f2()")


def f3():
    print("running f3()")


def main():
    print("running main()")
    print("registry ->", registry)
    f1()
    f2()
    f3()


if __name__ == '__main__':
    main()