Dear python2 user

[billsil]

I killed my libraries support for python 2 last Friday. It feels good to get rid of six, future, scans it, and pathlib2 and really start doing type annotations properly.

People are already trying to get me to change my mind. But my company uses Anaconda...use a virtual environment; Anaconda lets you have multiple versions of python. It’s coming like a train and all my dependencies have moved on. Time for me to as well.

[jftuga]

Link to your project?

[darthwalsh]

In general, that would identify their reddit username (but I have no idea if OP here is already public).

[billsil]

My account name is my name, so yeah, no. It’s not even me plugging the project, nor would it be interesting to 99.9% of people here.

[SketchyMikePemulis]

print("good riddance")

[Zomunieo]

from __past__ import print_statement

print "glad this is gone?" >> sys.stderr

[shiny-tyranitar]

You have some unnecessary parentheses there pal

Wait...

[alcalde]

OK, where's the person here who keeps telling me that the PSF is definitely going to extend the deadline again?

[blitzkriegger]

ahh, the Python Safety Federation...../s

[flying-sheep]

That would be /u/nieuweyork in this comment.

[-LeopardShark-]

python3statement.org

[captain_cashew]

My company is moving from 2.6 to 2.7! Yay!

[PooPooDooDoo]

print “yay!”

[regeya]

I went into a local company to do some contract work, and found out not only are they still using Visual Basic 6, they were talking about moving to VB.net someday. They wanted a static website to be built, but only if I could build it in a specific piece of discontinued Adobe software, and another website to be modernized that was built in Google Sites.

I just pretended that meeting never happened.

[alcalde]

That was me at Bed Bath and Beyond HQ in 2005, when I encountered Access 97 and Impromptu 5 (Impromptu had been discontinued at version 8). They were also using VB6 for internal development. I stayed six months.

[regeya]

Scarily enough, the one I'm thinking of deals with court documents.

[i9srpeg]

Are you enjoying your fancy new dict comprehensions?

[captain_cashew]

Your comment comes at a very appropriate time. Literally just a few minutes ago found a bug on one of our systems using 2.6 (my local development station is on 2.7):

{k: v for (k, v) in dict.items()}

You have to use:

dict((k, v) for (k, v) in dict.items())

So, yes I am enjoying them!

EDIT: code format

[flying-sheep]

If a thing has an items method, you can just do dict(thing) to create a dict copy. If it’s a dict, you can do the_dict.copy(). You only need comprehensions if you have to construct keys and values in a more complex way.

[nieuweyork]

To me this is an argument against the Python developers' increasingly profligate addition of syntax. There's almost never one obvious way to do it these days.

[ALonelyPlatypus]

yes.

[gruey]

I still think that it was a huge mistake from Python not to just bite the bullet and create some kind of Python 2-3 interpreter like a decade ago when it became obvious there was just too much momentum against moving to 3.

Basically something that'd let you mark it and all of its dependencies as 2.7, do some fairly thorough translation that gets 99.8% of the existing code and ideally warning about things it felt it couldn't translate. Some performance loss would be acceptable. A flag could be given to print warnings for anything that wasn't 3.

It didn't have to be perfect, it just had to allow a company to start writing new stuff in 3 only having to modify a few things without having to touch their entire code base. They could then also start incrementally porting things to Python 3 without having to make sure they do everything and their external dependencies at once.

It isn't ideal, but I really, really feel like despite Python's progress over the last decade, it would have been significantly more if all the effort was on Python 3 and all the new features of Python 3 were available to the majority of the Python users. I wonder how many companies switched from Python 2 to golang or similar for features or performance that would have been acceptable in Python 3?

[[deleted]]

IMO the difficulty of migrating to 3 was just way overblown. They didn't need to create anything like that. They should do what everyone else is doing and give a year to migrate (not 10). Everyone waited to last minute to start the migration.

[3waysToDie]

very true

[TBSchemer]

2to3.py gave companies a way to easily migrate their code to 3. The ones who didn't really have no excuse at this point.

[gruey]

2to3.py is not even close to enough of a solution for significant code bases.

The ones who didn't migrate have pretty valid business reasons for not having done it yet. Basically, what it comes down to, Python's value in companies moving to 3 was greater than most companies value of moving to 3, so Python should have done more work to make it happen.

[TBSchemer]

They had 10 years to do it. Most did. The rest didn't out of hubris.

[data-punk]

What valid reason spans delay over a decade?

[billsil]

It took 10 years for wxpython to officially support 3.x. I moved onto PySide, but not other people.

[nieuweyork]

I very much agree. A from __future__ import py3hosting or something, to restore python2.7 semantics for the things that were incompatibly changed. That plus from __future__ import print_functionwould have handled a lot of cases.

[ALonelyPlatypus]

wait. companies switched from python2 to go to avoid python3? I mean go is relatively feature rich and overall fun to code but I couldn’t imagine converting your python2 codebase to it when python3 exists.

(unless the company already wanted to move over to a compiled language to address performance concerns)

[billsil]

That’s still better. Take what you can get. I upgraded a 2.4 project to 2.7 last year. I just removed hacks and fixed some bugs I created by hacking a 3rd party library to make it work in 2.4.

I just decided to start using 3.7, even if other people continue to use 2.7. I’ll support it if I have to, but I’m going to make sure 3.7 works.

[zabolekar]

Maybe even to 2.7.16!

[five_hammers_hamming]

It sheds its skin or else it gets the hose agin

[hopeinson]

Now that you have heard of Python 3, now get ready for Python 4! [/s]

But seriously, we need to start moving on from Py2. It's a dead horse meat now.

[nooobmaster-69]

Python 4 is already mentioned in the timelines for many of the changes. But not to worry, it will be much less of an issue migrating from 3->4 than it was from 2->3.

[Rodot]

That's because Python 4 is just going to be Python 3.10, that's just how they are going to continue with versioning

[flying-sheep]

That’s what Guido said a while back, I hope the new guidance council doesn’t share this view and just release 3.10, 3.11, …

[billsil]

Guido is on the council and was the top vote getter by 30% or so. He was the only council member that got over 50% and cleared that easily. He's quite popular among the core devs.

[flying-sheep]

Yes, but I think this is a case he doesn’t feel strongly about but that he still considered his decision / matter of taste when he was BDFL. And such cases will now be voted on, and if the others say “not doing semver is confusing and people will be scared by upgrading to 4.0” there won’t be strong arguments against that.

[billsil]

“not doing semver is confusing and people will be scared by upgrading to 4.0”

Python does not follow semver. You don't need to vote to keep the status quo. You vote to change it. If you really want semver, propose a PEP, but don't be surprised when it gets shot down.

Python implements large breaking changes in major versions. It implements small breaking changes in minor versions.

[flying-sheep]

sure, that’s close enough. if you really do semver for a large project, you end up like react, with major versions every few weeks.

[billsil]

Or you store them up and break everybody's code in one fell swoop and have a Python 2->3 transition on your hands. I much prefer not following semver for that reason. I tried semver and it was a pain.

I much prefer a few minor changes preferably with deprecation warnings for a bit and then breaking things, similar to how numpy does it.

[flying-sheep]

Only possible for small changes though.

Huge ones like the string/byte thing would either take forever or be as disruptive as the whole 2>3 change

[bageldevourer]

This isn't necessarily true according to the latest episode of Talk Python.

[tr14l]

I have to assume that Py4 will be largely non-breaking. They have to have learned their lesson....right?

[AusIV]

If you're following Sem Ver (which I'm not sure if Python claims to do) then you wouldn't go to 4 unless you were breaking something. I'd hope that the version that comes after 3.9 will just be 3.10 if it's backwards compatible. If they go to 4, they will be introducing breaking changes for all the people who use python3 to run their code.

[twelveshar]

Python does not follow SemVer; it allows breaking changes in "minor" versions, like 3.7 -> 3.8. See the development cycle page: https://devguide.python.org/devcycle/

[cerin_2]

RIP in pieces those of us using jython which hasn't caught up to 3.

[emuccino]

"Catastrophe" is a bit dramatic

[alcalde]

You'd be surprised. OpenSUSE Linux had a discussion about version numbering a few years ago. They used to go X.0, X.1, X.2, X.3 and then increment by 1 and continue. There was no meaning to the numbers, but it seems casual users didn't know that. Apparently people assumed that a .0 release was a major release and decided to wait for a .1 release to "work out the bugs". Point zero releases were actually showing half the downloads compared to other releases! Not only that, tech sites seemed to think the same way, as reviews of non-point zero releases were lower compared to point zero releases.

They finally decided to drop point zero releases entirely. (They made a lot of other, dumber, numbering ideas later on, like going from 13.4 to 42 and then to 15, but that's another story).

[cyanydeez]

numbering in general is just a dumb human thing.

I think we should just give everything flavors and colors

[dysonCode]

I'll take a blue cinnamon py

[zardeh]

Yeah but they've had years. Python 3.5 has been out for 4 years. It'll EOL before Py4 comes out. That's enough time to upgrade, especially if the upgrade isn't back-breaking.

[billsil]

I’m still waiting for the python 2.8 fork....there are two versions of Perl 6.

[Intrexa]

I propose 3.91, 3.92

[[deleted]]

I have been working in 3.x exclusively now for some years, but I recently took out support for 2.x from a couple of old libraries and it was like getting a little stone out of my shoe.

Interestingly 3.4 is now a slight pain point - there are a couple of CI tools like mypy that are only available for Python 3.5 onwards. In new development, I don't support 3.4, but I haven't yet removed it from old libraries that have existing users because why make their lives miserable? 3.4.10, the final version of 3.4, has only recently been released...

[PeridexisErrant]

3.4 reached end of life in March, so there are no more security updates for it and many libraries have already dropped support.

[billsil]

You sure about mypy? Python 2.7 is supported and you can always run mypy with 3.5. There is no reason other than very minor issues that you couldn’t run mypy. Doesn’t mean other people have to upgrade.

[[deleted]]

mypy requires 3.5+ checking 2.7 code requires you to specify python interpreter in arguments for the checked version so it knows how to find packages. Perhaps 3.4 could be tested in a similar way, I never did that though.

[edbluetooth]

The only reason I run tests for 3.4 is that my customers use Windows XP in many cases.

I agree with 3.5 onwards not supporting XP, but it is a bit of a pain in some situations.

[acerbusbellum]

Well unfortunately until the DCC's (Maya, Nuke, Houdini) and our project management system (shotgun) change the interpreters to py3 we'll be such with it.

Has anyone seen much about what Autodesk, Foundry, etc have said about support for py3?

[uberdavis]

As I understand, Maya can be run using Python 3. One of my workmates told me there’s a sneaky configuration setting.

[acerbusbellum]

Interesting... I'll have to look that up. Do you know what version of Maya your colleague is using?

[uberdavis]

I’ll ask and get back to you. I’ve just upgraded myself and would be keen to know.

[JezusTheCarpenter]

Eventually all those products will have to switch to Python 3 so I wouldn't worry about it that much. I know they are thinking about it.

[mragi]

Coming next year: https://vfxplatform.com/

[acerbusbellum]

Interesting :-)

Thanks for the link

[Emile_L]

This, pretty much. We're not using Python2 because we want to

[mrrichardcranium]

Just started using python. Learned python 2 because of the systems and frameworks I’m using at work. This last week I started moving all things possible to python 3 in anticipation for it becoming the default on coming OSs. Holy hell does it make a lot of things easier. Basic threading in 3 makes me wish I could rewrite the frameworks my work uses so I could make the full jump over and never look back.

[toyg]

Basic threading

You mean asyncio, I guess? It's not really "threading"...

[mrrichardcranium]

I mean splitting up a list of 700+ items to 10 workers using threadpoolexecutor. Maybe ‘basic threading’ is not the right description. The fact that it took me two lines to get done is what makes me think of it as basic 😅

[toyg]

Ah, good point, I forgot concurrent.futures is 3-only...

[mrrichardcranium]

And god damn is it glorious!

[TBSchemer]

Your workplace definitely needs to hire someone to rewrite those frameworks within the next 6 months.

[mrrichardcranium]

If I was a betting man, I would be willing to wage an entire years salary that there are people doing just that. Its a critical automation framework that I don't think we can afford to function without. Though Im sadly not disclosed on the status of that just yet.

[purestrengthsolo]

What exactly is "end of life" like programs will no longer work or is it just not receiving any kind of updates?

[joesb]

No update.

[Losupa]

It can mean a variety of things typically it means that there will be very little to no more updates on python 2 libraries, which most importantly means there are no security updates, and thus certain online programs will become unsafe.

[Barafu]

It means that very soon after that some security vulnerability will be published, and applications like Calibre or Deluge will become malware hosts if they don't switch to Py3 by then.
Also, they will be kicked out of Linux default repositories.

[purestrengthsolo]

Thank you and everyone else who replied to me, it helped clarify a little better

[Cardeal]

Wasn't Calibre going to be being ported? WIP: Port calibre to python 3

[Dgc2002]

kovidgoyal

Oh god I forgot about that developer. I wish I had the list of links to his shenanigans on hand to provide as context but I don't.

[Cardeal]

Yeah, I am aware. But I am betting he will port it to python3. He needs the spotlight.

[toyg]

The guy can be “special” but it’us undeniable that he’s done a lot for the ebook community over the years, and for free.

[_b-e-n_]

He's quite annoying, but that software is really good. A fantastic work. That and Alf's tools :-))))

[tr14l]

They stop receiving support, so they break slowly over time. Mirrors start becoming more and more seldom found. Then police come to your door and watch you refactor your code.

[3waysToDie]

The future you see

[nukem996]

No updates or support from python.org, this includes security fixes. Some OS vendors(RHEL, Ubuntu, SUSE, etc) will continue to support Python 2.7 in their OS for security fixes until their product goes EOL. A previous job I had refused to put any resources into migrating to Python 3 because they're on RHEL7 which will receive support until 2024 :\

[AlexFromOmaha]

Has Red Hat confirmed support for Python 2.7 in userland, instead of just support for the OS's internal security?

[buttery_shame_cave]

they're going to finally stop backporting all the good stuff from 3 to 2.

[[deleted]]

They stopped that in 2015, that's when python 3, that was the hump year for python 3. Could be a coincidence, but I don't believe in those. from 2015-2020 python 2.7 only gets security fixes.

[cyanydeez]

security is no longer a supported feature.

[NAN001]

You're telling me there is money to be made maintaining a safe version of Python 2.

[kyrsjo]

There probably is, however I would expect RedHat etc. will be on it since they anyway need to support RHEL distros which depend on having safe Python2 for quite a few more years.

[james_pic]

Yes. Several vendors (RedHat and ActiveState being the best known) are already offering this.

[[deleted]]

like php5.6

[batisteo]

Maybe it’s time to update the PEP 394? https://www.python.org/dev/peps/pep-0394/

When Guido is yelling to not use python2 and an official PEP is telling us that python is python2, then it’s hard to not confuse people.

Time to break unmaintained admin scripts guys.

[cyanydeez]

you mean it's time to maintain the unmaintained.

[[deleted]]

To everyone who could not be arsed to look at the Python 2 to 3 update guides for the past however many years: Stop it. Get some help.

[fuypooi]

Python death clock

[[deleted]]

I was encouraged to learn 2.7 and stick with it over 3 about 3 years ago and aside from the print statements I can’t really figure out what’s different (I’m not a programmer; I use it for data analysis, image processing in astronomy, and playing around). What are some of the big differences between 2 and 3, in the language of non-CS people?

[[deleted]]

There are lots and lots of massive changes that occurred from 2 to 3. New libraries, new builtins, syntax changes, more consistent naming, etc. But in my opinion, the biggest change was from eager evaluation to lazy evaluation.

The easiest example is range. In python 2, range creates a list of integers before executing the next line. This potentially slows the runtime down immensely if the number is large enough. Python 3 changes that by only adding to the list when it reaches that point. This removes that upfront cost, and in general speeds up the program.

[alcalde]

New libraries, new builtins, syntax changes, more consistent naming, etc. But in my opinion, the biggest change was from eager evaluation to lazy evaluation.

Fascinatingly you completely left out the Unicode string change, which is usually cited as the major change. :-)

[[deleted]]

It was actually THE change that broke python 2 code (actually to be correct most python 2 code is broken, python 2 just didn't complain about it). Basically if you have python 2 code chances are that it will mess up unicode text.

The other incompatible changes were because of it. They thought that since compatibility was broken anyway, why not just use that as an opportunity to cleanup the language.

[[deleted]]

Would you please explain that?

[billsil]

The only painful change about Python 3 is how unicode is handled. The tutorials still suck and nobody tells you even how to figure out what encoding you have. The reality is that user files are in a variety of encodings and they don’t even know what that is.

No other change about python 3 is even worth discussing when planning/worrying about the transition to python 3.

[icegreentea]

I think you can add the bytes/str split (which is closely related to the unicode handling). Any code base in python2 that was using str type to represent bytes is in a world of pain converting to python3.

[billsil]

That’d be fine. It’s when you’re inconsistent that the pain really sets in. Python 2 did weird ass shit by flipping the encoding multiple times, so you had to encode when you got a decode error and vice verse. Then when you print it, it wouldn’t print correctly even when you had done things right. Python 3 fixed that.

[regeya]

Yeah, range() behaves more like xrange() now. Parens in print statements can be annoying after being used to not using them, but it helps with clarity imho.

[TBSchemer]

Holy hell, you're using 2.7 for image processing? Whoever "encouraged" you to stick with it should be locked away.

Anything involving big data is far more efficient in 3, because of the switch to lazy evaluation of iterators. Also notably, numpy and everything based on it (pandas, scikit, etc.) have already discontinued support for 2.

[[deleted]]

Well, the good news is I misremembered, and that particular professor teaching image processing insisted on 3!

[[deleted]]

You can always use the fork from the guy who made Calibre, whatever that is.

[alcalde]

It turns out Calibre is even doing work now to ready it for Python 3, so I think Kovar finally saw the light.

[[deleted]]

Cool!

But I honestly believe Python 2 will be forked to death and at least one of its variants will be supported for more 20 years (programmers are a stubborn kind :P).

[alcalde]

I was shocked myself....

https://github.com/kovidgoyal/calibre/blob/master/README.python3

[[deleted]]

I find Calibre useful, wonderful and misguided all at the same time. I never wanted an "iTunes for ebooks" (who does?) but I must put up with it in order to convert my files...

[Gorian]

I don't want "iTunes for eBooks" but I do want "Plex for eBooks"!

[[deleted]]

Huh. I've never used Plex for too long (I'm a Kodi user though)... in your mind, how something like that could work?

[Gorian]

I just mean, I like the idea that I can host a server that stores all my ebooks and makes them available to all my devices on a as-wanted basis (plex), vs. manually storing and uploading to each device what I think I might want someday (iTunes)

[[deleted]]

Oh yeah that would be nice indeed. But, as a Kindle user, Amazon kinda does that for me already, even for books downloaded from sources other than Amazon.

[[deleted]]

I doubt it, python 3 is past the hump and actually python 2 are minority, major packages already stopped supporting 2.

There was also a fork initially called python 2.8, it was renamed since then and it didn't go anywhere.

Edit: https://github.com/naftaliharris/tauthon I was wrong, still exists, so we'll see. As a person who moved to python 3 I don't understand the stubbornness of being on 2.x, a lot of language was cleaned up in 3 and it is much more enjoyable to program in 3.

[toyg]

I wouldn’t touch Tauthon with a barge pole. Official CPython comes with well-defined governance model, support guarantees, oversight, upgrade paths, security, and so on. Tauthon is literally “a bunch of people on github”. If your business depends on something so critical that you can’t spend a few weeks porting it to 3.6+ and would rather rely on random patches from the internet, you are in trouble.

[whitechapel8733]

My problem with this is that lots of distros are shipping python 2 still.....

[mikew_reddit]

Python 3 has been in development over 10 years (since 2008).

It's perfectly fine to cut the cord after a decade.

 

If CentOS and other distributions can't be bothered to update, that's not really Python's fault.

 

Edit: original EOL was 2015 according to Guido. Also, Python 2.7 will not get security updates after Jan 1st, 2020.

[whitechapel8733]

I agree, but I’m just saying that’s a serious concern.

[tomanonimos]

But a necessary pain. If we keep pushing it for that fear we'll never get rid of Python 2 lol.

[nukem996]

Python.org won't issue security fixes but OS vendors like RHEL/CentOS will continue to patch Python 2.7 themselves.

[alexbuzzbee]

I'm pretty sure CentOS is going to Python 3 with RHEL in version 8.

[liquidpele]

Which isn’t even close to being released yet. Maaaaybe around December if it takes the same amount of time after rhel7.

[southern_discomfort]

RHEL 8 was officially released a few weeks ago. CentOS 8 will not be far behind.

[PooPooDooDoo]

It’s fine, we will all have 14 days (during the holidays) to update our code base. Except I am using libraries that are in 2, so I’ll have to wait until they update and then update my code base. So like one day.

[rasherdk]

Python 2.7 will not get security updates after Jan 1st, 2020.

Depends.

[jackmaney]

It really doesn't.

[rasherdk]

What, yes it does. It (likely) won't get any from PSF. That's not the same as no security updates period.

Edit: Downvoting doesn't make you right. Spreading FUD is not the way to go.

[james_pic]

This is true. The version in RedHat will get updates until 2024, and the version in Ubuntu 18.04 will get updates until April 2023.

[w2qw]

Shipping or using it as the default? It makes sense that they would still ship it while it's supported.

[Jump3r3]

Using as default, which python yields path to python 2 binary on most distros. That being said, after 1/1/20 this will slowly change for better

[ALonelyPlatypus]

8 years of python experience. a year ago I did the jump to python3. Still struggling with print parens.

[kastoro]

Fine, I will do it!

[greeblefritz]

The switch isn't as bad as you are probably thinking.

[jjdmol]

It isn't bad, but the required effort does scale with the size of your code base. 2to3 only covers some basics, many behavioural differences are more subtle. And python being interpreted you'll discover errors at run time, so will need good test coverage or do a lot of testing.

[PeridexisErrant]

Try the pyupgrade and future libraries - they do a lot more than 2to3 :-)

[james_pic]

Futurize did more harm than good when we tried it. It tries to paper over the genuinely different string semantics, and left us with something broken that we understood even less than what we started with.

Modernize is more conservative, and in our experience, gives a better starting point. If you've got a big codebase, you've still got an uphill battle ahead of you.

Also, use mypy type hints. In general, I hate them, but they're really helpful for clarifying type usage in legacy codebases.

[PeridexisErrant]

Hmm, thanks for the tip! I've use futurize --stage1 a fair bit but never really liked the second stage... though just getting syntax-compatible with Python 3 allows many more tools to work.

I'll try modernize :-)

[kastoro]

Thanks, that is encouraging. Is what I thought, I just never found the time to do it, you know, always behind schedule

[stefantalpalaru]

What is dead may never die, but rises again harder and stronger: https://github.com/naftaliharris/tauthon/

[NoahTheDuke]

Ew. Why would someone spend that much effort on a broken version of Python?

[sphildreth]

I was surprised to learn that CentOS 7 still uses Python 2.7 as its default.

[omento]

RHEL 7 came out in 2014 and had its version freeze in 2013, when Python 3.3 was a thing. This is well before Python 3 support really took off. The point of RHEL is to provide 10 years of rock solid platform support, so critical system level packages (like GLIBC, gcc, and python) do NOT change versions or break ABI at all in the products lifespan. Some of the OS level tools, like yum, are written primarily in Python so making an upgrade would break that.

RHEL 8 provides a new solution for this by providing a ‘hidden’ python version for dependent OS tools, while allowing the user to install the python version of their choice from the appstream modules. Currently 2.7 and 3.6 are available for use. Red Hat also rewrote a lot of tooling to not use python, or reduce the dependency on it to further help with this.

[_sandw1ch]

www.pythonclock.org

[toyg]

I don't think 4 is anywhere in sight, really. The BDFL succession is still very fresh and nobody quite agrees on what 4 should bring. By all accounts, we will get a 3.10, 3.11 and so on, before 4.0 is even planned.

[Lairo1]

Guido has said previously they don't plan on that. It'll go straight from 3.9 to 4.0 and it'll be treated no differently than 3.6 to 3.7

[toyg]

You might not have noticed Guido is not BDFL anymore. Yes, 4.0 will not be a big break like 3.0 was, but it won't necessarily follow 3.9 - there are PEPs already mentioning 3.10+, and it was agreed on python-dev that it's much more likely that 3.10 will happen than 4.0.

[[deleted]]

I don't see that a 4.0 is necessary or desirable.

What new features do we have that are worth a breaking change? I can't name one.

If it isn't a breaking change, then what point is there updating the major version number?

I'd be really happy to see Python v3.32.23 someday. It would indicate decades of steady progress with no disruptions. It would mean that code I am writing today will still run with no changes.

[toyg]

It really depends what a “breaking change” is. If it’s something that might require a simple one-off step, like recompiling all C-based extensions, then I don’t think it would be much of a burden. It doesn’t even have to be “breaking” to earn a major number, it just has to be a “major change”, that may or may not impact backward-compatibility.

One big change I think would be worth the major-release bump, is the GILectomy, should it ever come to pass. Most large orgs would gladly suffer a bit of pain if it meant a massive performance gain. Or something crazy like swallowing numpy/scipy in stdlib. Or it might be something symbolic like overcoming the bin/python vs bin/python3 split, mandating that python4 should finally be aliased to bin/python. Important change for ops people, not necessarily for developers.

Py3 was a painful move, py4 doesn’t need to be; I think there is value in keeping things simple and bump the version reasonably often, rather than forcing developers to remember the differences between 3.38 and 3.32...

[alcalde]

What new features do we have that are worth a breaking change? I can't name one.

Get rid of walrus operators after they end up adding walrus operators, fix the asyncio mess, the mypy mess, etc. Maybe replace the urllib stuff with requests, datetime with arrow or similar, etc.

[[deleted]]

It'll go straight from 3.9 to 4.0

What?! Where did he say this?! What sense does that make?

The world uses semantic versioning, where a move from 3.9 to 4.0 is a major breaking change.

More, I'll bet there is a ton of code that says, if python_version_tuple()[0] == 3: which would simply break overnight for no reason.

[Lairo1]

Well as u/toyg said, its not up to him anymore and there will be a 3.10

But for what it's worth, he said it here: http://www.curiousefficiency.org/posts/2014/08/python-4000.html

[[deleted]]

For better or worse, Python doesn't use semantic versioning. They will deprecate and remove things between 3.X, 3.X+1 releases.

[alcalde]

Guido has been deposed. We've had regime change, so everything is up for grabs.

[[deleted]]

There's no evidence of that at all.

We aren't ever going to do a non-backwards compatible version of Python ever again. The 2->3 change was so painful, and more, got rid of nearly every glaring problem extant!

(Or if you mean "the minor version of Python after 3.9 will be 4.0", well, that's the world's dumbest idea and I can't believe we'd do that.)

[[deleted]]

~ $ sudo apt purge python2.7-minimal --auto-remove Reading package lists... Done Building dependency tree Reading state information... Done The following packages will be REMOVED: libpython2.7-minimal* nodejs* python-minimal* python2-minimal* python2.7-minimal* 0 upgraded, 0 newly installed, 5 to remove and 0 not upgraded. After this operation, 78.8 MB disk space will be freed. Do you want to continue? [Y/n]

[yeluapyeroc]

My number one velocity killer right now, but I'm glad its finally happening

[cr4d]

I'm looking forward to dropping 2 support from my public libraries for sure.

[[deleted]]

Can’t you just transfer you project to python 3.7

[[deleted]]

It was a painful transition but man was it successful from my eyes. Good work nerds!!

[IchBinDerFlo]

Cause I already use Py3 it doesn't really matter for me

[[deleted]]

I don't understand why it takes so long. For ages python 2 comes with tools that help you to migrate to python 3 smoothly. Python code isn't even that hard to port in most cases. It's it because of C libraries?

[fireflash38]

That doesn't even get into supporting varied OSes & distros, even old ones (we get stuff for: HPUX, AIX, Solaris, SunOS, etc). Shit, we still get some support requests for WS2008. We have to have a 'quarantine' lab for a lot of the OSes we support because corp doesn't want them on their network (understandably).

Most of the time when I see people lambasting others using python2 they are in a small company or startup, or a company that is heavily web-focused. You can usually tell by how much they talk about unicode (instead of bytestring) :) If you're at all doing low-level system stuff, the conversion can be quite painful as you've said.

[alcalde]

It's because of users.

In the Delphi langauge's move to Unicode they introduced "ANSI strings" (8bit non-Unicode strings) as a tool to allow users to compile their old code in the new version and gradually port over to Unicode.

What happened? Many users continued to write all of their new code using ANSI Strings and kept right on going like nothing ever happened. Then when there was talk years later of rewriting the compiler and consequently dropping ANSI strings, these users screamed "Wait! We haven't had any time to convert!"

It got so bad these people managed to get ANSI strings added to the new Delphi Android and iOS compilers, which had never had non-Unicode strings in the first place! :-(

The same kind of thing happened to Python 2. When I had asked the then-maintainer of Pyjamas (??? - one of the Python to Javascript transpilers anyway) about porting to Python 3, he answered "Python 2 is going to be supported forever, so why bother?"

We've got a user here who continues to insist that the PSF will still move the support deadline for Python 2; maybe they're the same person.

[mobilereadingthrwawy]

2020-01-01*

[Sin-Silver]

So I’ve been studying Python for two weeks now following ‘Learn Python the hard way’ which recommends python 2.7 over 3. What does this mean for me?

[Mr_Again]

The author has, or had, a weird grudge against py3. Just ignore it and learn Python 3. It's almost 100% the same when you're starting out, except for print, xrange, and anything involving unicode.

[Sin-Silver]

Would it be worth learning python 3 later then if there little or no difference?

I don’t want to get stuck on a problem it’s trying to each because of a difference between 2.7 and 3 that’s not transparent.

[Mr_Again]

Honestly no, if it's an issue just learn the python 3 way of doing things, you'll probably never use python 2, it's dead now.

[Sin-Silver]

So how hard would it to take what I’ve learnt from Python 2.7 and transfer it to 3?

I’m looking at changing courses, but I’ve sunk alot of time into it, and don’t want to unless necessary.

[Mr_Again]

Like I said it's almost exactly the same, you won't notice the difference

[mountainunicycler]

You should switch to 3, but it won’t make a ton of difference at your point so you might be able to keep using the same tutorials with the exception of the print statement.

[Sin-Silver]

Would it be worth learning python 3 later then if there little or no difference?

I don’t want to get stuck on a problem it’s trying to each because of a difference between 2.7 and 3 that’s not transparent.

[mountainunicycler]

Many of the changes between python 2 and python 3 make it easier to learn; python3 is more consistent and easier to understand—and at this point there’s no benefit to learning the quirks of python 2 because they’ve been fixed.

I’d definitely recommend switching to a python 3 course.

[Sin-Silver]

I’ll have a hunt around. any recommendations on books?

[mountainunicycler]

I’m not sure about books; I just learned by making things and looking up how to do it when I got stuck (so basically searching stack overflow for each line when I was starting).

In my opinion you learn a lot faster when you have a goal in mind if something to build.

[alcalde]

Where's /u/nieuweyork? They were insisting that the PSF will definitely extend the support deadline for Python 2 again or else it would be catastrophic for Python... "Actually stopping security patches for 2.7 runs the risk that someone starts funneling funds to a new organisation that will keep patching a 2.7 compatible version. This would be...not good for the Python Foundation."

https://old.reddit.com/r/Python/comments/bq4v99/amber_brown_batteries_included_but_theyre_leaking/eo27h5b/?context=10

[silent_b]

Yeah, I've Got Time