Python でUTF-8, shift_jis, euc_jp,など日本語を使う方法

#!/usr/bin/env python
# -*- coding: utf-8 -*-

import codecs

fin  = codecs.open('utf_8.txt', 'r', 'utf_8')
fout = codecs.open('sjis.txt', 'w', 'shift_jis')

for line in fin:
    fout.write(line)