[Python-Dev] proposed os.fspath() change

[Koos Zevenhoven]

>>     if isinstance(filename, os.PathLike):

By the way, regarding the line of code above, is there a convention
regarding whether implementing some protocol/interface requires
registering with (or inheriting from) the appropriate ABC for it to
work in all situations. IOW, in this case, is it sufficient to
implement __fspath__ to make your type pathlike? Is there a conscious
trend towards requiring the ABC?

-- Koos