How to use multiple versions of Python without uninstallation

Question

I am faced with a unique situation, slightly trivial but painful.

I need to use Python 2.6.6 because NLTK is not ported to Python 3 (that\'s what I could gather).

Answer 1

You simply install multiple versions in separate directories, and then you run the python program with the Python version you want to use. Like so:

C:\Python26\Python.exe thescript.py

Or similar.

What virtualenv does is that it gives you many separate "virtual" installations of the same python version. That's a completely different issue, and hence it will not help you in any way.