title: python pexpect sendcontrol key characters
body: <p>I am working with pythons pexpect module to automate tasks, I need help in figuring out key characters to use with sendcontrol. how could one send the controlkey ENTER ? and for future reference how can we find the key characters?  </p>
  
  <p>here is the code i am working on.</p>
  
  <pre><code>#!/usr/bin/env python
  
  import pexpect
  
  id = pexpect.spawn ('ftp 192.168.3.140')
  
  id.expect_exact('Name')
  
  id.sendline ('anonymous')
  
  id.expect_exact ('Password')
  *# Not sure how to send the enter control key
  id.sendcontrol ('???')* 
  
  id.expect_exact ('ftp')
  
  id.sendline ('dir')
  
  id.expect_exact ('ftp')
  
  lines = id.before.split ('\n')
  
  for line in lines :
          print line
  </code></pre>