["python","django","django-templates"]
How to do math in a Django template?

I want to do this: 100 - {{ object.article.rating_score }} So for example, the output would be 20 if {{ object.article.rating_score }} equaled 80. How do I do this at the template level? I don't have access to the Python code.
You can use the add filter: {{ object.article.rating_score|add:"-100" }}