如何使用Python pexpect模块自动执行shell交互命令

pexpect 我可以做到这一点,但我无法实现我所希望的结果。我正在尝试以下代码,有人可以指导我如何实现这一点,因为我是python初学者。任何帮助都将不胜感激。我的应用程序设置如下所示

[root@bits packages]# ./SHR_setup.bin -i console
    Preparing to install...
    Extracting the JRE from the installer archive...
    Unpacking the JRE...
    Extracting the installation resources from the installer archive...
    Configuring the installer for this system's environment...

    Launching installer...

    ===============================================================================
    Choose Locale...
    ----------------

        1- Deutsch
      ->2- English
        3- Español
        4- Français
        5- Italiano
        6- Nederlands
        7- Português  (Brasil)

    CHOOSE LOCALE BY NUMBER: 2
    I accept the terms of the License Agreement (Y/N): Y
    Please hit Enter to continue:

from pexpect import pxssh
import pexpect

    try:
        s = pxssh.pxssh()
        hostname = '10.110.40.20'
        username = 'admin'
        password = 'admin123'
        s.login(hostname, username, password)
        s.sendline('cd /var/packages')   # goto /var/packages folder
        child = pexpect.spawn('./SHR_setup.bin -i console')  # start the application setup in packages folder
        child.expect('CHOOSE LOCALE BY NUMBER')   # expect output like this 
        child.sendline('2')   
        s.prompt()
        print s.before
    except pxssh.ExceptionPxssh, e:
        print 'pxssh failed on login'
        print e