OT:
I know that Django 1.6+ can be used with Python 3.4 but is Django 1.7.1 written in Python 2.7 or 3.4?
I know that Django 1.6+ can be used with Python 3.4 but is Django 1.7.1 written in Python 2.7 or 3.4?
It is possible, and not too difficult in fact, to write a single codebase that runs under both Python 2 and Python 3. Which is what Django has done. The same code runs the same under 2.7 or 3.3 or 3.4.
Are there any guidelines or "best practices" for writing code for both 2.7 and 3.4?
This is a pretty comprehensive guide. It does rely on the future lib, which is a wrapper around six and a few others to make it easier, but you can also just write your own minimal lib for things that need to have:
if py2:
pass # Py2 specific line here
else:
pass # Py3 stuff here