multithread.py

import threading
import time


def func1():
    print('Starting func 1')
    end_time = time.time() + 5

    i = 0
    while time.time() < end_time:
        i += 1

    print(f'func 1 counted {i}')
    print('func 1 done')


def func2():
    print('Starting func 2')
    end_time = time.time() + 5

    i = 0
    while time.time() < end_time:
        i += 1

    print(f'func 2 counted {i}')
    print('func 2 done')


def func3():
    print('Starting func 3')
    end_time = time.time() + 5

    i = 0
    while time.time() < end_time:
        i += 1

    print(f'func 3 counted {i}')
    print('func 3 done')


if __name__ == '__main__':
    threads = [
        threading.Thread(target=func1),
        threading.Thread(target=func2),
        threading.Thread(target=func3)
    ]
    for thread in threads:
        thread.start()

    for thread in threads:
        thread.join()

singlethread.py

import time

if __name__ == '__main__':
    end_time = time.time() + 5

    i = 0
    while time.time() < end_time:
        i += 1

    print(f'counted {i}')