python中telnetlib模块的使用方式

#encoding=utf-8
 
def do_telnet(Host, username, password, finish, commands):
    import telnetlib
    '''Telnet远程登录：Windows客户端连接Linux服务器'''
 
    # 连接Telnet服务器
    tn = telnetlib.Telnet(Host, port=23, timeout=10)
	tn.set_debuglevel(2)
     
    # 输入登录用户名
    tn.read_until('login: ')
    tn.write(username + '\n')
    
    # 输入登录密码
    tn.read_until('password: ')
    tn.write(password + '\n')
      
    # 登录完毕后执行命令
    tn.read_until(finish)
    for command in commands:
        tn.write('%s\n' % command)
    
    #执行完毕后，终止Telnet连接（或输入exit退出）
    tn.read_until(finish)
    tn.close() # tn.write('exit\n')
 
if __name__=='__main__':
	 # 配置选项
	Host = '10.255.254.205' # Telnet服务器IP
	username = 'administrator'   # 登录用户名
	password = 'dell1950'  # 登录密码
	finish = ':~$ '      # 命令提示符
	commands = ['echo "test"']
	do_telnet(Host, username, password, finish, commands)

    import threading
    pars = replace_db_keyworlds(vars_dict, pars)
    configs = pars.split(r'@')
    host = configs[0].encode()
    user = configs[1]
    passwd = configs[2]
    finish = configs[3]
    commands = configs[4].split(r'\n')
    th1 = threading.Thread(target=do_telnet, args=(host.encode('utf-8'), user.encode('utf-8'), passwd.encode('utf-8'), finish.encode('utf-8'), commands))
    th1.start()
    th1.join(20)  ##20秒超时时间