Drop support for Python 2

[hugovk]

Python 2 reaches end-of-life on 2020-01-01.

See https://python3statement.org for a list of projects which have pledged to drop support for Python 2 on or before its EOL.

I'd like to suggest making a release soonish with the recent changes that still supports Python 2.7, and then drop it.

That'll allow newer features of Python to be used, and also some vendored code can be removed (eg. #362 (comment)) and deal with some other issues (eg. #268 (comment)).

[claudep]

+1. What would you suggest for the next version numbering, 0.13.1?

[hugovk]

I don't know the version scheme being used so far, but if we look at the popular SemVer:

4. Major version zero (0.y.z) is for initial development. Anything MAY change at any time. The public API SHOULD NOT be considered stable.

5. Version 1.0.0 defines the public API. The way in which the version number is incremented after this release is dependent on this public API and how it changes.

...

How do I know when to release 1.0.0?

If your software is being used in production, it should probably already be 1.0.0. If you have a stable API on which users have come to depend, you should be 1.0.0. If you’re worrying a lot about backwards compatibility, you should probably already be 1.0.0.

Tablib was downloaded nearly 300,000 times last month, I think it's about time for 1.0.0 :)

[claudep]

I'm not very comfortable releasing 1.0.0 right now, I'd rather stick with 0.13.1 or 0.14.0 and release 1.0.0 after dropping Python 2. Thoughts?

[hugovk]

Agreed. (I mixed up the next release with the drop release.)

SemVer says:

• For 0.y.z releases, anything goes.

• For 1+.y.z releases, bump the patch number x.y.Z when there's bugfixes.

• For 1+.y.z releases, bump the minor number x.Y.z when there's new features (and optionally also bugfixes).

I'd probably go for 0.14.0.

[peymanslh]

Hello @hugovk @claudep
Can I work on this issue and send a pull request?

[claudep]

Fine for me. It will probably need some rebasing at the time we're ready to commit it.

[peymanslh]

I sent a pr: #394
@claudep

[claudep]

PR #394 was merged "manually".