python 装饰器学习

示例1：最简单的函数，表示调用了两次
>>> def myfunc():
...     print("myfunc() called.")
... 
>>> myfunc()
myfunc() called.
>>> myfunc()
myfunc() called.

示例2：替换函数（装饰）
装饰函数的参数是被装饰的函数对象，返回原函数对象
装饰的实质语句: myfunc = deco(myfunc)‘‘‘


>>> def deco(func):
...     print("before myfunc() called.")
...     func()
...     print(" after myfunc() called.")
...     return func
... 
>>> def myfunc():
...     print(" myfunc() called.")
... 
>>> myfunc = deco(myfunc)
before myfunc() called.
 myfunc() called.
 after myfunc() called.
>>> myfunc()
 myfunc() called.
>>> myfunc()