import threading
import time

start = time.perf_counter()

def do_something(seconds):
    print(f'Sleeping {seconds} second(s)...')
    time.sleep(seconds)

threads = []
if __name__ == '__main__':
    for _ in range(10):
        t = threading.Thread(target=do_something,args=[1.5])
        t.start()
        threads.append(t)

for thread in threads:
    thread.join()

finish = time.perf_counter()
print(f'Took {round(finish-start,2)} seconds.')