In the past have been developed for example nose2pytest module which provides possibility to filter existing nose test suites based code and more or less automatically port it to use with pytest.
Someone maybe saw some similar tools which provided filtering existing six code and more or less automatically port it to use with with latest standard modules?
There are as well some changes for example between python 3.8.x and >= 3.9.
Someone have been thinking and/or maybe developed some tools make easier to at least encircle fragments which could be rewritten to latest pythons versions?
You might also want to consider Ruff, which implements all the Pyupgrade autofixers as well as hundreds of others, while running much faster due to being written in Rust. Additionally, I’m currently working on infrastructure that will allow exposing a substantial substantial amount of information on additions, changes, deprecations and removals to the language in programmatic form, which such tools could then consume to even more comprehensively identify, and in some safer automatically resolve, changes between Python versions.
I don’t see anything in ruff about upgrade code which uses six.
It is yet another issue with ruff. I cannot build it because final linking fails with thousandths missing symbols (many rust code is COMPLETLY USELESS when LTO is used).
Ruff should be available in the package managers of many mainstream distros (though not Debian stable, it seems), and is built and tested with LTO by default in release mode. If you run into issues building it, you might want to search or ask about your issue on the various Ruff communication channels (issue tracker, forums, etc). At least from what I’ve seen, Charlie Marsh and the other Rust maintainers are quite active, friendly and helpful on this Discourse and elsewhere responding to issue reports, particularly if the issue is with Ruff and not your bespoke config.
Per six’s own documentation, six.MAXSIZE is equivalent to sys.maxsize all the way back to Python 2.6 through present-day Python 3; the constant in six is only necessary for compat with Python 2.5, which hasn’t been relevant for well over a decade by now.