import time, functools
def metric(fn):
    #@functools.wraps(metric)
    def inner(*args, **kwargs):
        a=time.time()
        res = fn ( *args,**kwargs)
        b=time.time()
        print('%s executed in %s ms' % (fn.__name__, b-a))
        return res
    return inner

#以下为测试部分
@metric
def fast(x, y):
    time.sleep(0.001)
    return x + y;

@metric
def slow(x, y, z):
    time.sleep(0.1)
    return x * y * z;

f = fast(11, 22)

s = slow(11, 22, 33)
if f != 33:
    print('测试失败!')
elif s != 7986:
    print('测试失败!')
else:
    print('测试成功!')