py2 str == py3 bytes py2 unicode == py3 str The problem with this approach is that they wanted to reuse the `str` name, which requires a big "flag day", where

py2 str == py3 bytes py2 unicode == py3 str The problem with this approach is that they wanted to reuse the `str` name, which requires a big "flag day", where it switches meaning and compatibility is effectively impossible across that boundary (without ugly hacks). What they could have done instead would have been to just rename `str` to `bytes`, but retain a deprecated `str` alias that pointed to `bytes`. That would keep old scripts running indefinitely, while hopefully spewing enough warnings that any maintained libraries and scripts would make the transition. Eventually they could remove `str` entirely (though I'd personally be against it), but that would still give an actual transition period where everything would be seamlessly compatible. Same thing with literals: deprecate bare strings, and transition to having to pick explicitly between `b"foo"` and `u"foo"`. Eventually consider removing bare strings entirely. DO NOT just change the meaning of bare strings while removing the ability to pick the default explicitly (in contrast, 3.0 removed `u"asdf"`, and it was only reintroduced several versions later). What made me personally lose faith in the Python Core team wasn't that Guido made an old mistake a long time ago. It wasn't that they wanted to fix it. It was the absolutely bone-headed way that they prioritized aesthetics over the migration story.