title: How to get the seconds since epoch from the time + date output of gmtime()?
body: <p>How do you do reverse <code>gmtime()</code>, where you put the time + date and get the number of seconds?</p>
  
  <p>I have strings like <code>'Jul 9, 2009 @ 20:02:58 UTC'</code>, and I want to get back the number of seconds between the epoch and July 9, 2009.</p>
  
  <p>I have tried <code>time.strftime</code> but I don't know how to use it properly, or if it is the correct command to use.</p>