Get list of commands and run them in parallel.

parallel.py

import os, sys, time
from concurrent.futures import ThreadPoolExecutor
from threading import Thread

class WorkThread(Thread):
    def __init__(self, data):
        Thread.__init__(self)
        self.data = data
    def run(self):
        os.system(self.data)

def start(data):
    thread = WorkThread(data)
    thread.start()
    thread.join()

if len(sys.argv) < 2 or sys.argv[1] == "-h" or sys.argv[1] == "--help":
    print("python3 script {file} {workers} {sleep}")
    exit()

delay = 0
workers = int(sys.argv[2])
if len(sys.argv) > 3:
    delay = int(sys.argv[3])

with open(sys.argv[1]) as file:
    first_cycle = True
    times = 0
    data = file.read().split("\n")
    with ThreadPoolExecutor(max_workers=workers) as executor:
        for d in data:
            if first_cycle:
                times += 1
                time.sleep(delay)
                if times > workers:
                    first_cycle = False
            executor.submit(start, d)