It's just about backward compatibility. If you don't run the exact version of python that's running in production, how do you know that you're not using some me

It's just about backward compatibility. If you don't run the exact version of python that's running in production, how do you know that you're not using some method that does not exist in production yet (because you run older version there)? Also, libraries with binary component often have to be compiled against specific version of python.