subprocesses_in_threads.py

#!/usr/bin/env python3

import time
import subprocess as sp
import concurrent.futures as cf

start = time.time()

with cf.ThreadPoolExecutor() as e:
    futures = [e.submit(sp.check_output, f"sleep 2s && echo Done {i}.", shell=True) for i in range(3)]
    for future in cf.as_completed(futures):
        print(future.result())

end = time.time()

print(f"The whole thing took {end-start} seconds.")