Example with lock thread

thread_lock.py

""" Worker will wail to another to finish a task in order to do some procedure
"""
import threading
import logging
import time
logging.basicConfig(level=logging.DEBUG,
                    format='(%(threadName)-10s) %(message)s',)


def worker(lock, seconds=2):
    logging.debug('Waiting for lock if it exists')
    with lock:
        logging.debug('Lock acquired')
        time.sleep(seconds)
    logging.debug('Lock freed')


if __name__ == '__main__':
    lock = threading.Lock()
    w1 = threading.Thread(target=worker, args=(lock, 2))
    w2 = threading.Thread(target=worker, args=(lock, 1))

    w1.start()
    w2.start()

A link reference for the future