argument against pythonic `dict.get` `template_tag`

I’m running a django project that uses a webpack manifest to retrieve the name of the appropriate webpack asset. I created a context processor, however because the key is dynamic, in the context of the template I need to “get” the value accessible via that key in a python dict. The Django builtin template_tags are pretty slim and I started wondering: why isn’t there a dict.get template tag? I saw this thread and I think I understand the philosophy that as much context as possible should be given before the view renders the template, however I’m curious if there are any obvious security (or otherwise) concerns in creating a pythonic get template tag?

I don’t see why there would be, unless templates are written by non-programmers or are not retrieved from the filesystem. I’ve build such a filter myself too.