[Biopython-dev] Planning to drop Python 2 support by 2020?

[Peter Cock]

Thanks for the clarification Joao,

I have only started using Python 3 as my main version of Python
this year - and am aware that the need to continue to support
Python 2.7 in Biopython has constrained me from adopting some
of the new features in Python 3.x.

Even if we do eventually drop Python 2 support in 2020, we would
not actively remove or prevent people using the older releases of
Biopython. We can explicitly list the final Python 2 compatible
release on our download page too, as I would not be surprised to
have a fraction of people continuing to use Python 2 beyond 2020.

While I would want to make any commitment to do so at this point,
I would likely be sympathetic to creating a branch should there be
a strong case for an extra point release to address an important bug.
I think that would be consistent with the spirit and wording of the
pledge on http://www.python3statement.org/

So, do you agree with Biopython signing up to that pledge?

Regards,

Peter

On Thu, Jun 22, 2017 at 11:19 AM, João Rodrigues
<j.p.g.l.m.rodrigues at gmail.com> wrote:
> Hi Peter (and all),
>
> Don't take me wrong. I do agree that it is a good idea, I just think it's
> very hard to implement in practice. As I mentioned in the other thread, I
> work with code written in the 80s, that's how it is in some fields. I only
> recently moved to Python 3.x because I got a new laptop and decided to take
> the plunge... all my code works with Python 2 and I rarely make use of 3.x
> features (maybe I should?). I had to do some fixing to some of my scripts
> but that's because I wrote them and I am fairly familiar with the language.
> A user of a script or of a library would very likely not know how to fix it,
> and we all know how often zombie code survives after the original developer
> moved on to another lab/position. Regardless, as Tiago mentioned, many other
> Python libraries will drop support anyway so we'll be left behind. He's
> right.
>
> My only recommendation would be to have a release that supports Python 2.x
> and keep that available for download. Perhaps even still support it
> regarding bug fixing, but freeze any new features. This way we can still
> support any users left with Python 2.x on their systems, whether because
> upgrading causes a bunch of problems or because they are actually
> technically incapable of doing it themselves, or both.
>
> Cheers,
>
> João
>