<s>[INST] 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 to do this at the template level? I don't have access to the python code.
 [/INST] You can use the add filter:
{{ object.article.rating_score|add:"-100" }}

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