[tlug] Supporting Old Versions of Python 2 (was Re: perl? (was: Employment for "oldies"))

[jep200404@example.com]

On Thu, 18 Aug 2016 15:37:11 +0200, Attila Kinali <attila@example.com> wrote:

> I wrote my first python
> scripts around python 2.4. Which current distro still has a 2.4 version around?
> Even with debian/stale, the oldest version you get is a 2.7. So your
> only choice is either python 2.7 or 3.x. What am I going to do with
> that script I wrote 5 years ago?

Explore conda (miniconda or anaconda).

There has long been the problem of different Python projects
needing different versions of Python packages. For Python,
a solution has been to use virtualenv with which each
project can have different versions of the same package.
You can also specify which (already installed) Python to use,
but it does not make the installation of different versions 
of Python easy. A newer version of virtualenv is
pyvenv or venv.

Conda is similar, but makes it easy to install and use different
versions of Python for different projects. I don't see any 2.4 
versions listed below from the output of the conda search python
command. The oldest 2 series release listed, 2.6.8, was released on 
2012-04-10, less than five years ago. For a script written for
the current stuff five years ago, do you find a compatible version?

Also, virtualenv and conda allow one to separate the Python and
packages that a project uses from what the operating system uses.

You have been using Python longer than I. Within the Python 2
series, how much have you seen a newer release break old code?
I have understood that they try to maintain backward compatibility
within the Python 2 series, but I do not have enough experience
to know what the exceptions have been. What breakage have you 
experienced (or heard about) within the Python 2 series?

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