title: django: how to do calculation inside the template html page?
body: <p>Hi I am using thumbnail plugin to get the image's width and height, now I want to define the padding of the img tag using the gotten height from thumbnail plugin, like:</p>
  
  <pre><code>&lt;img style="padding-top: {{ img.height / 2 }}" src=""/&gt;
  </code></pre>
  
  <p>But I got error here, does django not allow calculate like this?</p>