运行时间装饰器

def run_time(func):
    def new_fun(*args,**kwargs):
        t0 = time.time()
        print('star time: %s' % (time.strftime('%x', time.localtime())))
        back = func(*args, **kwargs)
        print('end time: %s' % (time.strftime('%x', time.localtime())))
        print('run time: %s' % (time.time() - t0))
        return back
    return new_fun