Is there a standard way to make sure a python script will be interpreted by python2 and not python3?

Question

Is there a standard way to make sure a python script will be interpreted by python2 and not python3? On my distro, I can use #!/usr/bin/env python2 as the shebang, but it se

Answer 1

This is a bit of a messy issue during what will be a very long transition time period. Unfortunately, there is no fool-proof, cross-platform way to guarantee which Python version is being invoked, other than to have the Python script itself check once started. Many, if not most, distributions that ship Python 3 are ensuring the generic python command is aliased by default to the most recent Python 2 version while python3 is aliased to the most recent Python 3. Those distributions that don't should be encouraged to do so. But there is no guarantee that a user won't override that. I think the best practice available for the foreseeable future is to for packagers, distributors, and users to assume python refers to Python 2 and, where necessary, build a run-time check into the script.