Python 3.3.5 has been released

http://docs.python.org/3.3/whatsnew/changelog.html

by adamnemecek • 12 years ago

85 46 12 years ago

docs.python.org

null_ptr• 12 years ago

So what's the deal with Python these days? Do people still write for 2.7 which is the default "python" in most (all?) Linux distributions, or is it safe to write for python3 now?

viraptor• 12 years ago

Do people still write for 2.7

Yes.

which is the default "python" in most (all?) Linux distributions

Most distributions ship both 2.x and 3.x at the same time. Ubuntu ported most (all?) of its tools to 3.x already.

is it safe to write for python3 now?

What do you mean by safe? It's been stable for a long time now. As long as you verify all your dependencies work, you should be fine. The only annoying thing you may run into is a situation where only one of the versions is provided: for example if you want to drive ufw (3.x only) from salt (2.x only), you'll have to resort to some kind of IPC instead.

There was a poll about the current state a month or two ago on HN.

wfn• 12 years ago

Also, python3 is the default in archlinux: https://wiki.archlinux.org/index.php/python

raverbashing2• 12 years ago

Yes, Python 3.3 is absolutely fine, I wouldn't bet on 3.2 or anything earlier though.

yeukhon4• 12 years ago

Yes. Like any other Python 2 releases, there are always new syntax and function additions. I think the only major Python library people use not available on Python 3 is Twisted. (edit: I think Mercurial is also not compatible with Python 3 IRRC due to byte-string and unicode incompatibility). Even Tornado and pyCurl works with Python 3 (according to pypi and doc).

Before you start writing in Python 3, make sure your dependencies will run on Python 3.

leobelle2• 12 years ago

Twisted is a library you might want to use if you want to write non-blocking code. So you would care a great deal if this wasn't python 3 if you wanted to use python 3.

Mercurial is an application you use to version control your source. I'm not sure I understand why any python developer would care if Mercurial was written in python 2 as long as it worked. Maybe if someone was writing a Mercurial plugin or patching Mercurial they would care.

dagw• 12 years ago

I think the only major Python library people use not available on Python 3 is Twisted.

The problem is rarely the major libraries, it's that one obscure minor library that almost no one (except you in your Very Import Application) uses.

rogerbinns• 12 years ago

Amazingly people still use Python 2.3. With source downloads you can't tell what platforms use, but you can with binary downloads. One of my projects is a Python wrapper for SQLite (APSW) for which I also provide compiled Windows binaries for every Python version from 2.3 to the latest, and 64 bit for some of them too. It is very amusing to me that some people want the latest SQLite while using a positively ancient Python version.

Google code shows download counts so you can get an idea of popularity of each release for Windows developers:

https://code.google.com/p/apsw/downloads/list?can=1&q=&colsp...

I've since moved the project to github which doesn't show the download counts for releases.

https://github.com/rogerbinns/apsw/releases

ambiate• 12 years ago

We still use python2.0-2.5. Various versions for various libraries. It is hell.

zem• 12 years ago

definitely not all distributions, arch has 3.x as default and 2.7 as python2

wylee• 12 years ago

I think it's pretty safe to go with Python 3 for new and/or personal projects. I started moving all my stuff to Python 3 a few months ago and Fabric is the only major project I use that hasn't been ported.

thomasahle• 12 years ago

It's actually getting a lot better. Many distributions ship python3 as the default python now, and even libraries like numpy and interpreters like pypy support it.

est2• 12 years ago

I hope CPython could introduce more performance improvements, not just bug fixes and alternative features.

alialkhatib• 12 years ago

That'd be nice, but since CPython is supposed to serve as a reference implementation (and not necessarily be the bleeding edge of speed) I don't hold much hope of performance improvements becoming a top priority (except to make Python3 more compelling than Python 2.x strictly on performance criteria, which they've largely accomplished if I understand correctly).

est2• 12 years ago

So CPython think performance is about politics, but tell you what, it's also about competition. Every new Ruby release has some kind of performance tweak, Rubinius got rid of GIL entirely, Nodejs and V8 is significantly faster than pure Python, Go is one of the fastest.

rectangletangle• 12 years ago

The widespread use of generators in 3 helps with performance. And the new asyncio in Python 3.4 should help with IO bound applications. If that isn't enough there's PyPy, a JIT compiled Python implementation.

lucian1900• 12 years ago

Except PyPy is Python2, so that won't help either.

If you want performance, Python 2 and PyPy is what you're looking for.

eddd• 12 years ago

Guido can release python 7, and still minority will use it, since many libs (https://python3wos.appspot.com/) are not ported to python 3.

makmanalp3• 12 years ago

That list sure is turning greener and greener every day. It's getting harder to use that as an excuse. I think my next project, I'll start using py3. The main big ones I see are boto (has a partial 3k fork that isn't official yet) and mysql-python (looks pretty dead, shame).

Quite a few others like Gevent and supervisor, for example, have py3k ports nearly done, and mostly await merging.

rodelrod2• 12 years ago

MysqlDB was holding me back from Python3, but that problem was settled with Oracle releasing a Python connector for MySQL [1] that works for both Python 2.x and 3.x. It's a solid and very complete library and it's DB-API compliant, so that migrating from MysqlDB can be pratically seamless.

[1] https://dev.mysql.com/downloads/connector/python/

tragic• 12 years ago

It seems like in the time I've been using python (about 18 months, really) the community has really stepped up the pressure to switch to 3.x. The vast majority of what I use day-to-day has now been ported (just noticed Paramiko support has been merged to master two days ago[1], so Fabric'll follow rapidly after that), and every time I see a new book come out it demands Python 3.

I will try to be a good boy and use it going forward (I already find it more useful for CSV and other file I/O type tasks thanks to the unicode support, but am reliant on mysql for some routine drudgery as well).

[1] https://github.com/paramiko/paramiko/pull/276

mildtrepidation3• 12 years ago

"Excuse" seems like a loaded word to use here. It's a valid reason when your dependencies don't work or haven't been thoroughly tested in Python 3.

daGrevis2• 12 years ago

I started new project on Python 3 yesterday and I can say that there hasn't been any problems so far. Libraries I needed to use were compatible with Python 3: toml, markdown and Jinja2. I'm looking forward to use clint for better CLI as well! Everything was solid and production-ready. It's good to know that some really weird things are fixed in new Python. I can't think of any reason not to start new app in Python 3! :)

mildtrepidation3• 12 years ago

I can't think of any reason not to start new app in Python 3!

Sorry, but my recent experience has not matched yours, so the fact that this particular project had no library compatibility issues does not mean they no longer exist.

I'm glad you found a project you can use it on. That just doesn't mean much to those of us who are still hitting the same familiar issues with it.

daGrevis2• 12 years ago

Yes, libraries that you may need may not be compatible yet. But it is fair to say that situation is getting better.

Also, here's a great tool that checks if you can use Python 3: https://caniusepython3.com/ .

raverbashing2• 12 years ago

Unless you depend in a big library that doesn't support Python 3 (and they're getting rare), I would suggest moving

Then the ones left behind can be adapted, tested, or alternatives found, and the whole ecosystem can move on.

If we keep using Python 2 to be safe nothing will change.

Using Django and Python 3 and so far it's been a breeze, with minor bumps.

cm127• 12 years ago

Wanna get people to really start using Python 3? Make it the default version on Ubuntu LTS.

https://wiki.ubuntu.com/Python/3

rlpb• 12 years ago

Python 3 is already available by default on Ubuntu. The page you link to refers to the removal of Python 2 by default, which is a separate thing, since both can be installed at once.

As for making Python 3 the default if you type "python", this is unlikely to happen, for compatibility reasons: http://legacy.python.org/dev/peps/pep-0394/

rcxdude• 12 years ago

Yeah, Arch does this and it breaks so many things (any PKGBUILD which involves python will have some hack or another to fix things).

hit8run• 12 years ago

Python 3.4.0 final: March 16, 2014

I think I'll wait for 3.4 to land in a few days and from then on use py3 instead of 2.7 :)

agumonkey• 12 years ago

I forgot how close to the release date we were already. Joy.

Python 3.3.5 has been released

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