import time
def set_func(func):

    def call_func(*args, **kwargs):
        start_time = time.time()
        func(*args, **kwargs)
        end_time = time.time()

        print('use time:%i' % int(end_time - start_time))
    return call_func


@set_func
def sss():
    time.sleep(4.0)

if __name__ == '__main__':
    sss()

结果：

use time:4