I thought about that, usually I would add the path and then import it BUT in this case func is very simple (at least that's how I thought about it). 

For example here's what it looks like in zaunteam:

ALDRYN_SEARCH_LANGUAGE_FROM_ALIAS = lambda alias: alias.split('-')[-1]

to me a function in a module would be overkill. We could do both, what do you think ?