How do I tell a Python script to use a particular version

python version virtualenv
jesuis picture jesuis · Jun 23, 2012 · Viewed 169.2k times · Source

How do I, in the main.py module (presumably), tell Python which interpreter to use? What I mean is: if I want a particular script to use version 3 of Python to interpret the entire program, how do I do that?

Bonus: How would this affect a virtualenv? Am I right in thinking that if I create a virtualenv for my program and then tell it to use a different version of Python, then I may encounter some conflicts?

Answer

Gravity Grave picture Gravity Grave · Jan 27, 2017

Perhaps not exactly what you asked, but I find this to be useful to put at the start of my programs:

import sys

if sys.version_info[0] < 3:
    raise Exception("Python 3 or a more recent version is required.")

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