don't you just love it when you're using a library, and they have a 230 lines of code method
and somewhere in the middle of that method it creates a context dict that you want to extend with extra fields
it's something that's generally meant to be user extendable
it's something that the library devs could've expected a user might want to add fields to
but there's no way to do so
there's also not any method that's called later on that you could override and insert the fields there, which would be ugly but at least it would get the job done
so you're left with having to subclass that class and copy the entire 230 lines of code of that method (+ the imports) just to patch in a "get_context" method that you can then override in your own class to add the extra fields
this is normal to do :^)