python 自带2to3.py 代码转换2-->3

2to3.py

#!/usr/bin/env python
import sys
from lib2to3.main import main

sys.exit(main("lib2to3.fixes"))

demo.py

def greet(name):
    print "Hello, {0}!".format(name)
print "What's your name?"
name = raw_input()
greet(name)

　　

执行命令:

python 2to3.py  demo.py 显示差异

　

python 2to3.py -w demo.py 修改文件,源文件会被命名为demo.py.bak