Update obsolete installed packages

update_packages.py

#!/usr/bin/env python3
import json
import subprocess
import sys


def grab_packages():
    process = subprocess.run([sys.executable, "-mpip", "list", "-o",
                              "--format=json"] + sys.argv[1:],
                              capture_output=True)
    return [package["name"] for package in json.loads(process.stdout)]


def update_packages(packages):
    if not packages:
        print ("Everything is up to date")
    else:
        subprocess.run([sys.executable, "-mpip", "install", "--upgrade"] +
                       sys.argv[1:] + packages)

if __name__ == "__main__":
    # Invoke with --user to update user packages
    update_packages(grab_packages())