Python version(s) for new project?

[Philip Semanchuk]

Hi all,
I'm about to start a new job at which I and others will build a  
project largely in Python. I'm trying to figure out which Python  
versions to use and support. I can't use Python 3.x, but I want to  
prepare for it even if it is a long way off yet.

My idea is to use Python 2.6 on my development box and 2.4/2.5 on the  
test machines. This would allow me to use the -3 switch on my machine  
so that I keep the code relatively free of features unsupported or  
deprecated in 3.x. It will also ensure that I write code backwards  
compatible with older Python versions.

Does this sound sane?

My constraints:
- Need to support Linux and Windows
- I'll be developing under OS X (thank you VirtualBox!)
- Using wxPython, scipy, numpy, SWIG
- Code will eventually be open sourced

Thanks
Philip