python wait for thread to finish
t1 = Thread(target=call_script, args=(scriptA + argumentsA))
t2 = Thread(target=call_script, args=(scriptA + argumentsB))
t3 = Thread(target=call_script, args=(scriptA + argumentsC))
t1.start()
t2.start()
t3.start()
# join() stalls program execution until the thread stops executing
t1.join()
t2.join()
t3.join()