def outer(fun):
  print fun
  def wrapper(arg):
    result=fun(arg)
    print 'over!'
    return result
  return wrapper
@outer
def func1(arg):
  print 'func1',arg
  return 'very good!'
response=func1('python')
print response
print func1

<function func1 at 0x02A67D70>
func1 python
over!
very good!
<function wrapper at 0x02A67CF0>

#!/usr/bin/env python
#coding:utf-8
def Filter(before_func,after_func):
  print before_func
  print after_func
  def outer(main_func):
    print main_func
    def wrapper(request,kargs):
      before_result=before_func(request,kargs)
      if(before_result!=None):
        return before_result;
      main_result=main_func(request,kargs)
      if(main_result!=None):
        return main_result;
      after_result=after_func(request,kargs)
      if(after_result!=None):
        return after_result;
    return wrapper
  return outer
def before(request,kargs):
  print request,kargs,'之前！'
def after(request,kargs):
  print request,kargs,'之后！'
@Filter(before,after)
def main(request,kargs):
  print request,kargs
main('hello','python')
print main

<function before at 0x02AC7BF0>
<function after at 0x02AC7C30>
<function main at 0x02AC7CF0>
hello python 之前！
hello python
hello python 之后！
<function wrapper at 0x02AC7D30>