[Python-Dev] Bring new features to older python versions

["Martin v. Löwis"]

> The first one is about licensing.
> What I would be doing is basically copy&  paste pieces of the python
> stdlib modules (including tests) and, where needed, adjust them so
> that they work with older python versions.
> Would this represent problem?

You have a "nonexclusive, royalty-free, world-wide license to ..."
"prepare derivative works, distribute, and otherwise use Python alone or 
in any derivative version," so: no, this is no problem ...

"provided, however, that PSF's License Agreement and PSF's notice of 
copyright, i.e., "Copyright (c) 2001, 2002, 2003, 2004, 2005, 2006, 
2007, 2008, 2009, 2010, 2011 Python Software Foundation; All Rights 
Reserved" are retained in Python alone or in any derivative version 
prepared by Licensee."

> My second doubt is about morality.
> Although this might be useful to those people who are forced to use
> older python versions, on the other hand it might represent an
> incentive for not upgrading (and there will be python 3.X features as
> well).

Don't worry about that. I'm not sure how many people would be interested
in your approach in the first place - if I have to support old versions
of Python, I personally just don't use newer features, and don't even
have the desire to do so. If I want to use newer features, I decide to
drop support for older versions. That I get both with a hack as such
a module is just something that I *personally* would never consider
(there are other reasons for me to consider hacks like this, such as 
when supporting multiple versions is just not feasible, but I wouldn't
use a hack for convenience reasons).

People that do feel the same way as you have probably started their
own emulation layers already, so by publishing your emulation layer,
it's not getting worse.

Regards,
Martin