[docs] [issue34051] Update multiprocessing example

Antoine Pitrou <pitrou@free.fr> added the comment: To be frank, I don't think that matters much. The user should understand what a lock is already, if they want to make use of multiprocessing fruitfully. The example showcases how to create a lock and how to pass it to child processes (by giving it as a function parameter). Printing to standard output is not the important thing here. However if you want to improve this example, you could replace the acquire/release pair with a "with" statement. ---------- _______________________________________ Python tracker <report@bugs.python.org> <https://bugs.python.org/issue34051> _______________________________________