How to Port from Python 2 to Python 3 (2019)

#1

Post by noego » Thu, Jan 23, 2020, 1:14 PM UTC

How to Port from Python 2 to Python 3 (2019)
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Re: How to Port from Python 2 to Python 3 (2019)

#2

Post by o_x » Thu, Jan 23, 2020, 1:32 PM UTC

Isn't it ironic that Sentry is one of the tools mentioned in py2->py3 migration? (Sentry is on py2 and as far as I remember they were not very optimistic about migrating)

Re: How to Port from Python 2 to Python 3 (2019)

#3

Post by LoreleiPenn » Thu, Jan 23, 2020, 1:33 PM UTC

Hopefully no more people will keep saying "learn Python 2 because 3 has almost no packages".

It is so easy for people to just repeat what they heard even if that idea originated a decade ago and was valid a decade ago.

And that way we got into a mess of not migrating until pass the time it is no longer supported...

Re: How to Port from Python 2 to Python 3 (2019)

#4

Post by swalsh » Thu, Jan 23, 2020, 1:35 PM UTC

I literally just got on a phone call to discuss our migration away from 2.7, very timely post.

Re: How to Port from Python 2 to Python 3 (2019)

#5

Post by ryandvm » Thu, Jan 23, 2020, 2:04 PM UTC

Python 3 and IPv6 are the poster-children of how _not_ to do a major upgrade. I'm not sure what the right way is, but if the short-term advantages of the upgrade do not outweigh the immediate pain, prepare for the matter to drag out for _decades_.

Re: How to Port from Python 2 to Python 3 (2019)

#6

Post by zitterbewegung » Thu, Jan 23, 2020, 2:09 PM UTC

The big issue of ports like these is not the tutorial but to justify that to your boss.

From enterprise to a self run startup you have to see if it’s worth it .

Re: How to Port from Python 2 to Python 3 (2019)

#7

Post by rb808 » Thu, Jan 23, 2020, 2:13 PM UTC

ryandvm wrote: post #5

Python 3 and IPv6 are the poster-children of how _not_ to do a major upgrade. I'm not sure what the right way is, but if the short-term advantages of the upgrade do not outweigh the immediate pain, prepare for the matter to drag out for _decades_.

At least Python3 brings an improvement. I still can't think of a good reason I should spend any time trying to figure out IPv6. Maybe my external router has to think about it, but that is about it.

Edit: If you down vote me please say why I should care about IPv6

Re: How to Port from Python 2 to Python 3 (2019)

#8

Post by badsectoracula » Thu, Jan 23, 2020, 2:14 PM UTC

ryandvm wrote: post #5

Python 3 and IPv6 are the poster-children of how _not_ to do a major upgrade. I'm not sure what the right way is, but if the short-term advantages of the upgrade do not outweigh the immediate pain, prepare for the matter to drag out for _decades_.

> I'm not sure what the right way is

The right way is to make sure that stuff that used to work in the previous version still works in the current version. Breaking people's work, especially work that spans multiple years, projects, knowledge, etc and expecting them to be happy about it is naive. Being condescending when they turn out to not be happy and try to avoid the unnecessary busywork forced on them does not help either.

This isn't just about Python, many libraries and languages (and some OSes - see iOS, macOS and to a slightly less extent Android) are terrible about this. The proliferation of semver with its normalization of breaking stuff (the fact that a dependency - be it a library or language or whatever - uses semver communicates that they have already decided that they will break backwards compatibility at some point) shows that most people are fine with breaking others' code.

Re: How to Port from Python 2 to Python 3 (2019)

#9

Post by zojirushibottle » Thu, Jan 23, 2020, 2:19 PM UTC

o_x wrote: post #2

Isn't it ironic that Sentry is one of the tools mentioned in py2->py3 migration? (Sentry is on py2 and as far as I remember they were not very optimistic about migrating)

that's correct. sentry itself is on python 2.7, not the python client.

not to pick on sentry here, but you know, my experience is that people are having a hard time migrating due to them using obscure tricks and features of python 2.7. so their code is breaking because the language evolved.

the saying goes write dumb code or something because debugging is twice as hard. if there is anything to learn from all this, it's to write dumb code because maintenance is twice as hard too.

that's all that is happening really!

Re: How to Port from Python 2 to Python 3 (2019)

#10

Post by Fr0styMatt88 » Thu, Jan 23, 2020, 2:26 PM UTC

rb808 wrote: post #7

ryandvm wrote: post #5

Python 3 and IPv6 are the poster-children of how _not_ to do a major upgrade. I'm not sure what the right way is, but if the short-term advantages of the upgrade do not outweigh the immediate pain, prepare for the matter to drag out for _decades_.

At least Python3 brings an improvement. I still can't think of a good reason I should spend any time trying to figure out IPv6. Maybe my external router has to think about it, but that is about it. Edit: If you down vote me please say why I should care about IPv6

The main mental stumbling block I have about IPv6 (and I know it's kind of a silly one, but it's honestly what I feel on introspection) is that I can't remember an IPv6 address off by heart. IPv4 addresses just _feel_ so much more human-consumable than IPv6 addresses. I can't imagine myself using IPv6 addresses on the command line like I do with IPv4 now.

There's also the issue that honestly, I have no idea what is using IPv6 and what's using IPv4 right now. On my internal network I only ever deal with IPv4, but I have no intuition as to what is using IPv6; I couldn't tell you off the top of my head if my ISP supports it.