> They didn't always want to migrate because their userbase was generally mostly on 2. Yes, this doesn't change my argument. You had 12 years of warning. You c

> They didn't always want to migrate because their userbase was generally mostly on 2. Yes, this doesn't change my argument. You had 12 years of warning. You couldn't migrate immediately, but you had 12 years of warning to plan your migration. > I think the next backwards incompatible change in python (python 4?) will probably see a much bigger migration off python. You aren't paying much attention to the python ecosystem then. I wouldn't expect a python3-like breaking change for another 10 years, if ever. > Mercurial, built on python, took 10 years of work to get to python 3 - for basically no reward (they just need bytes and unicode is not super relevant to them) as just one example of MANY. Mercurial took ~4.5 years to migrate, from April 2015 to November 2019. Mercurial also took a roundabout way of doing the migration that likely made it take longer (https://gregoryszorc.com/blog/2020/01/13/mercurial%27s-journey-to-and-reflections-on-python-3/ https://gregoryszorc.com/blog/2020/01/13/mercurial%27s-journ...) > The python developers literally TOOK THIS AWAY in python 3. And then readded in python 3.3, around 7 years ago. > . You couldn't practically move initially. Something as simple as doing u'' in python 2 that would alias properly in 3 - was a no go. I agree you couldn't migrate immediately! But you still had 12+ years of warning! I'll repeat myself: I expect most application code was migratedn in the last 2 years. But the maintainers of those applications had 10+ years to prepare for the migration of their application. This prep took many forms. For some it was nothing, for some it was helping dependencies migrate to 2/3 compat. For some it was planning the eventual migration. But every single one had more than a decade of warning.