import time,functools

def log(func):

 @functools.wraps(func)

 def wrapper(*args,**kw):

  t1=time.time()

  r=func(*args,**kw)

  print('%s excute in %s ms'(func._name_,1000*(time.time()-t1)))

  return r

 return wrapper

@log

def fast(x,y):

 return x*y

fast(3,5)