single_thread.py

from threading import Thread
import time

def count():
    i = 0
    for _ in range(50000000):
        i += 1
    return True

def main():
    thread_table = {}
    start_time = time.time()
    for tid in range(4):
        t = Thread(target=count)
        t.start()
        thread_table[tid] = t
        t.join()
    end_time = time.time()
    print("Total time: {} secs".format(end_time - start_time))

if __name__ == '__main__':
    main()

# Total time: 13.2221679688 secs