title: Error: no "view" mailcap rules found for type "application/pdf" pythonanywhere server log
body: <p>I'm trying to Use lolviz and graphviz to visualize data structures, but there is no output. This is the error I get in server logs: groupn.pythonanywhere.com.server.log</p>
  
  <pre class="lang-none prettyprint-override"><code>Warning: 2017-11-14 16:32:24 Illegal attribute sides in &lt;TD&gt; - ignored 2017-11-14 16:32:24   
  Warning: 2017-11-14 16:32:24 Illegal attribute sides in &lt;TD&gt; - ignored 2017-11-14 16:32:24 in label of node node140165832004944 2017-11-14 16:32:24   
  Warning: 2017-11-14 16:32:24 Illegal attribute sides in &lt;TD&gt; - ignored 2017-11-14 16:32:24 in label of node node140165832024136 2017-11-14 16:32:24   
  Error: no "view" mailcap rules found for type "application/pdf" 2017-11-14 16:32:24 /usr/bin/xdg-open: 461: /usr/bin/xdg-open: 2017-11-14 16:32:24   
   links2: not found
  </code></pre>
  
  <p>This is where the function is in my views.py</p>
  
  <pre><code>elif 'show' in request.POST:
                  data = callviz(s).view(filename=None, directory=None, cleanup=True)
                  return render(request, 'file/stacks.html', {'form': form, 'data': data})
  </code></pre>