How do I dynamically switch between default Python versions?

I know this question already exists, but it's really old and I开发者_JS百科 know what I'm looking for. I've used an application earlier that let me very easily install any version of Python and set it to default with one command. I can't for the life of me remember the name, and for some reason I can't find it via Google either!

You're looking for PythonBrew, perhaps?