就改个函数名就不能运行了

Question

原函数：import timedef performance(unit):    def perf_decorator(f):        def wrapper(*args, **kw):            t1 = time.time()            r = f(*args, **kw)            t2 = time.time()            t = (t2 - t1)*1000 if unit =='ms' else (t2 - t1)            print 'call %s() in %f %s'%(f.__name__, t, unit)            return r        return wrapper    return perf_decorator改完以后：@perforimport timedef performance(unit):    def g(r): def wa(*args,**kw): r1=time.time() f=r(*args,**kw) r2=time.time() t=(r2-r1)*1000 if unit=='ms' else(r2-r1) print 'call %s() in %f %s'%(r.__name__, t, unit) return f return wa return g@performance('ms')  def factorial(n):    return reduce(lambda x,y: x*y, range(1, n+1))print factorial(10)