the Gravity of Python 2

[Chris Angelico]

On Thu, Jan 9, 2014 at 1:30 AM, Mark Lawrence <breamoreboy at yahoo.co.uk> wrote:
> But to be serious why not stick with 2.x if there's no compelling reason to
> move?  Whatever happened to "if it ain't broke, don't fix it"?  And before
> anyone says anything please don't start on about the bytes versus string
> debate, I'm fairly certain that there are a substantial number of
> application areas that don't run into these problems.

Two reasons for moving:

1) Support for newer hardware, underlying libraries, etc
2) Bug fixes and security patches.

#1 won't be a visible problem for most people - they'll be using a
Python packaged by their OS, so if there are any issues with building
Python against version X.Y of libfoobar, the OS maintainers will
either ship the older version of libfoobar, or make Python work. Only
a handful of people (the OS package maintainers themselves) will even
need to consider that. So it's #2 that people will be thinking about.
There's going to come a time when python.org will no longer provide
updates for Python 2.7, and at that point, everyone has to decide
which is greater: the risk of undiscovered flaws, or the hassle of
shifting. For most end users, they'll choose to stick with an
unsupported Python rather than shift, but there are those (corporates,
mainly) for whom a promise of bug fixes is critical, so that'd be
their date to shift. After all, it worked for Windows XP, right?
End-of-life date rolls around and everyone moves onto Windows 7....
hmm, maybe that didn't quite happen. Still, it does put pressure on
people.

ChrisA