If wanting to know up front if this is designed for the future or the past is an edge case, it's a pretty crowded edge. Python 3 was released eight years ago, and I will ALWAYS choose a competing technology (if it means a language other than Python, that's fine with me) before I'll let Python 2 play any role in a new project I architect.

The first thing I looked for on the Bokeh website was some sort of clear statement on the front page about it being Python 3. I don't have an immediate need for it, but if it's Python 3, I'll keep it in mind. If it's just that euphemistic "Python", it may as well be Cobol for all I'd care.

I thought I'd skim over these comments just in case someone asked the obvious question, and someone did. (Thank you.) And, yes, it is apparently Python 3 enough that we wouldn't need to use any Python 2 if we adopted it.

Very nice. Now I wish I DID need it, but maybe I'll do a side project of my own with it, just for fun. I'll be keeping it in mind in any case. I'll bet "Python 3" is mentioned somewhere on the site, but I didn't spot it right away. It might be worth making it a bit more prominent, since it is an important feature for those designing for the future.