Ubuntu 16.04 LTS is going to be Python 3 by default. I switched to Python 3 only a year ago. The war is over, Python 3 won, and now it's just the "too big to fail" guys who still think Python 2 has a future. Google, Dropbox and a few others who will probably give it another5 years before they make the switch using 3.5's type hints to help automate the process of moving to Python 3.

There was never a war, and Python 3 didn't win it.

We're still not seeing any mainstream Python 3 adoption (no, I don't count your own project). PyPI downloads was still < 5% last I checked. The big web frameworks are still better tested and better performant with 2. Scientific computing is stuck with 2. Same with Ansible. And the big companies you mention have no (public) intention to migrate.

The core developers decided long ago that 3 is what everyone should use, so I have no doubt that will be the case. The open question is how much is left of the ecosystem by then. It's commonly discussed at conferences but there is no straightforward answer. At least we got the TLS stuff backported to 2 which might be indicative of a coming thawing.

I don't understand how python's leadership works but from my outsider perspective it seems like the solution is that those with some power need to show some muscle in forcing a direction. I mean this has been going on for 7 years now, someone needs to lay down the law.

If you introduce a new developer to Python the first step is "ignore Python 3, nobody uses that" and then explain that there's infighting about backwards incompatibility so most packages either don't support it or do it badly. Why do I have to justify to new talent the reasons why I'm using a language that can't even agree on the latest version?

> We're still not seeing any mainstream Python 3 adoption

I think mainstream adoption is increasing, but not as quickly as anyone would like. The sentiment around adoption I felt echoed at PyCon this year was: "we have dependencies that aren't ported to 3 yet [... and who will be the ones to port them?!]".

The Python 2 codebase is growing much faster than Python 3, because the Python core developers have lost touch with the fact that its most dedicated users are not web people, but scientific computing users for who the overwhelming choice is 2.7. Anaconda gives you a 3.x choice on its website almost as an afterthought. Theano is half hearted on 3. Bloomberg doesn't even have a 3 access library (goodbye 3.0 for the entire finance sector). Asyncio, one of the so called killer features of 3, looks great but is 10 years too late and is done much better in other languages (goroutines). Python is seriously losing momentum: hey, even Hacker News quickly demoted this story to page 2 precisely because it attracted the usual flood of 2v3 comments causing the comment number to dwarf the score. It's become a controversial and uncool language thanks to this forced 3 story, and the fact that 6 years later in this dog-years world, this issue is still on the table, makes 3 an utter failure.

I predict that 2.7.9.x.y.z will continue well past 2020 and backport any truly useful stuff from 3 because that's much easier than porting 2 code to 3. Or, and the core developers should seriously think about this, they should build 2->3 right into the interpreter so you can run, unmodified 2.7 code on a 3 interpreter (2.7 libraries included), and then pick and choose the 3 features you want yourself.

> Scientific computing is stuck with 2.

False. NumPy, SciPy, scikit-learn, Pandas, and friends all work great on Python 3.

It's not a question whether it works. It's a question of whether it's being used. And it's not, really. Those code paths are less tested and less performant, so why would you choose them even if you start a new project without baggage?

Python 3 won't see any traction unless it offers a clear improvement over 2. Some people think that's async. I have my doubts.