python实现telnet客户端的方法

import getpass
import sys
import telnetlib
HOST = "hostname"
user = raw_input("Enter your remote account:")
password = getpass.getpass()
tn = telnetlib.Telnet(HOST)
tn.read_until("login: ")
tn.write(user + "\n")
if password:
  tn.read_until("Password: ")
  tn.write(password + "\n")
tn.write("ls\n")
tn.write("exit\n")
print tn.read_all()