Changing the existing functions is a no-go for backwards compatibility reasons. I think the best way forward would be to add a new function, and then possibly deprecate the old one if it's deemed dangerous.

If you want to push this forward, could you summarize the use case(s) and expected behavior (docs) for such a function? It probably doesn't need a PEP, but it's worth looking here for what to think about when making a proposal: https://www.python.org/dev/peps/pep-0001/#what-belongs-in-a-successful-pep