import functools
def log(text):
    def decorator(func):
        @functools.wraps(func)
        def wrapper(*args,**kw):
            if text==None:
                print('%s'%func.__name__)
            else:
                print('%s'%text)
            return func(*args,**kw)
        return wrapper
    return decorator

@log('execute')
def f():
    print('2016-8-7')
f()
print(f.__name__)

运行结果

execute 2016-8-7 f [Finished in 0.2s]