You can check the version of Python that is running a program, at runtime.

First you need to import the sys module from the standard library:

import sys

Then check the content of the sys.version_info property.

This property returns the Python version as a tuple.

>>> sys.version_info
sys.version_info(major=3, minor=9, micro=0, releaselevel='final', serial=0)

Python lets you compare tuples, so you can check for example if the current Python version is 3.7.0 or higher:

sys.version_info >= (3, 7)

You can add this check in a conditional then, to quit the program when a Python version is too old:

if sys.version_info < (3, 7):
    print('Please upgrade your Python version to 3.7.0 or higher')
    sys.exit()

Lessons in this unit:

0:	Introduction
1:	Introduction to Python
2:	Installing Python 3 on macOS
3:	▶︎ How to check the current Python version
4:	Running Python programs
5:	Python 2 vs Python 3
6:	The basics of working with Python
7:	Python Data Types
8:	Python Operators