title: DownloadError: ApplicationError
body: <p>I have a function called DownloadData() which uses <code>url.fetch()</code>. 
  From time to time it throws <code>DownloadError: ApplicationError: 2 timed out error</code>. </p>
  
  <p>How can I catch this error?
  With <code>except DownloadError: ApplicationError: 2 timed</code> or only <code>DownloadError</code>?<br>
  It is hard to reproduce this error so I can not know which except to use.</p>
  
  <p>Thanks,</p>
  
  <p>Joel</p>