Update all packages of a given package manager sequentially

update.py

#!/usr/bin/env python3

import subprocess
import platform
import sys


class Update:
    def __init__(self, list_packages_cmd: str, update_package_cmd: str):
        self.list_packages_cmd = list_packages_cmd
        self.update_package_cmd = update_package_cmd

    def fetch_upgradable_packages(self):
        output = subprocess.run(self.list_packages_cmd.split(), capture_output=True).stdout.decode()
        self.packages = [line.split(" ")[0] for line in output.split("\n")]
        self.package_count = len(self.packages)
        return self

    def upgrade_all(self):
        for package in self.packages:
            self.upgrade(package)

    def upgrade(self, package: str):
        subprocess.run(f"{self.update_package_cmd} {package}".split())


if __name__ == '__main__':
    if len(sys.argv) <= 1:
        print("Please pass the command to list upgradable packages and the command to upgrade a single package.")
        print("If your package manager is pacman then a valid call would be: ./update.py 'pacman -Qu' 'sudo pacman -S'")
        exit("ERROR: Not enough arguments!")

    update = Update(sys.argv[1], sys.argv[2])
    update.fetch_upgradable_packages().upgrade_all()