title: Send input to command line prompt from Python program
body: <p>I believe this to be a very simple question, but I have been failing to find a simple answer.</p>
  
  <p>I am running a python program that terminates an AWS cluster (using starcluster).  I am just calling a command from my python program using subprocess, something like the following.</p>
  
  <pre><code>subprocess.call('starcluster terminate cluster', shell=True)
  </code></pre>
  
  <p>The actual command is largely irrelevant for my question but provides some context.  This command will begin terminating the cluster, but will prompt for a yes/no input before continuing, like so:</p>
  
  <pre><code>Terminate EBS cluster (y/n)? 
  </code></pre>
  
  <p>How do I automate typing yes from within my python program as input to this prompt?</p>