python注释文件内容

1、怎么注释文件文件

文件内容

1.1.1.1 good idea
192.168.1.214  xxx.com
192.168.201.48 xxx.com
192.168.201.48 xxx.com
python代码

#/bin/env python
#coding:utf-8
import re

w_str=''
with open('./file','r+') as fobj:
    for line in fobj.readlines():
        line = re.sub('^','#',line)
        w_str+=line
        print w_str

with open('./file','wb') as fobj:
    fobj.write(w_str)
输出结果：

#1.1.1.1 good idea
#192.168.1.214  xxx.com
#192.168.201.48 xxx.com
#192.168.201.48 xxx.com