Python-Day4实现简单的shell sed替换功能

code：

 1 f = open(‘yesterday‘,‘r‘,encoding=‘utf-8‘)
 2 f2 = open(‘yesterday.bak‘,‘w‘,encoding=‘utf-8‘)
 3 old_str = input(‘请输入要修改的字符：‘)
 4 replace_str = input(‘请输入替换成的字符:‘)
 5 for line in f.readlines():
 6     line = line.replace(old_str,replace_str)
 7     print(line)
 8     f2.write(line)
 9 f.close()
10 f2.close()

文件内容：（yesterday）

Somehow, it seems the love I knew was always the most destructive kind
不知为何，我经历的爱情总是最具毁灭性的的那种
Yesterday when I was young
昨日当我年少轻狂
The taste of life was sweet
生命的滋味是甜的
As rain upon my tongue
就如舌尖上的雨露

感想：

　　思路很简单就是打开源文件，然后循环，把源文件要替换的内容替换再写入新文件！