title: File tests in Python?
body: <p>I'd like to use Python 3.3.3 to test for the existence of a backup file.</p>
  
  <p>Something like this:</p>
  
  <pre><code>if backup does not exist:
      create it
      write to backup
  
  otherwise:
      run other procedures not related to backup file
  </code></pre>
  
  <p>Any suggestions?</p>