title: pexpect - can't run example, kept getting AttributeError: 'module' object has no attribute 'spawn'
body: <p>I am running Python3 and been trying to run sshls.py script but always fail with:</p>
  <h3>AttributeError: 'module' object has no attribute 'spawn&quot;</h3>
  <p>I tried running as:</p>
  <pre><code>python3 sshls.py
  </code></pre>
  <p>I even modified the script to set either env or python script but still fails:</p>
  <pre><code>#!/usr/bin/python3
  </code></pre>
  <p>OR</p>
  <pre><code>#!/usr/bin/env python3
  </code></pre>
  <p>I tried with python2.7 and still get same error.</p>
  <p>Content of script:</p>
  <pre><code>from __future__ import print_function
   
  from __future__ import absolute_import
   
  import pexpect
  import getpass, os, traceback
  def ssh_command (user, host, password, command):
       ssh_newkey = 'Are you sure you want to continue connecting'
       child = pexpect.spawn('ssh -l %s %s %s'%(user, host, command))
       i = child.expect([pexpect.TIMEOUT, ssh_newkey, 'password: '])
       if i == 0: # Timeout
           print('ERROR!')
           print('SSH could not login. Here is what SSH said:')
           print(child.before, child.after)
           return None
       if i == 1: # SSH does not have the public key. Just accept it.
           child.sendline ('yes')
           child.expect ('password: ')
           i = child.expect([pexpect.TIMEOUT, 'password: '])
           if i == 0: # Timeout
               print('ERROR!')
               print('SSH could not login. Here is what SSH said:')
               print(child.before, child.after)
               return None
       child.sendline(password)
       return child
   
  def main ():
       host = &quot;www.example.com&quot;
       user = &quot;root&quot;
       password = &quot;password&quot;
       child = ssh_command (user, host, password, '/bin/ls -l')
       child.expect(pexpect.EOF)
       print(child.before)
   
  if __name__ == '__main__':
       try:
           main()
       except Exception as e:
           print(str(e))
           traceback.print_exc()
           os._exit(1)
  </code></pre>