Better handling of Unicode was also why Python3 adoption has been slow. Upgrading a library or project from Py2 to Py3 is very simple if you already handle byte

Better handling of Unicode was also why Python3 adoption has been slow. Upgrading a library or project from Py2 to Py3 is very simple if you already handle bytes vs unicode carefully everywhere in your program. But for projects that mix unicode and byte strings, and hope for the best (it works okay as long as it is ASCII or UTF8), the upgrade requires substantial work.