A quick question about Jinja2 filters... I have auto escaping turned on, so
I have to use the safe filter to explicitly turn off escaping. I have
written a few filters that I know will always produce safe output, let's
call one of these "foo".

In my templates, I often do something like {{ my_var|foo }}, forgetting
that I need to add safe at the end, e.g. {{ my_var|foo|safe }}.

My question: is it possible for my foo filter to indicate that it's output
is already safe, so that it is not necessary to add the safe filter
explicitly?