Python打开文件，接受命令行

# -*- coding: UTF-8 -*-
import os
import sys
import traceback
if len(sys.argv)<2:
print "参数0",sys.argv[0]
print " 必须输入参数"
sys.exit(0)
try:
name =sys.argv[1]
if os.path.exists(name):
input = open(name,'r')
for line in input:
print line,
except Exception,e:
print traceback.print_exc()