How can I use queues in Python with multithreading?

How can I use queues in Python with multithreading?

You can use the queue module in Python to create a thread-safe queue. This allows multiple threads to add and remove items safely.

Can you show me a simple example of using a queue with threads?

Sure! Here's a basic example:

import threading
import queue

# Create a queue
q = queue.Queue()

# Worker function
def worker():
    while True:
        item = q.get()
        if item is None:
            break
        print(f'Processing {item}')
        q.task_done()

# Create threads
threads = []
for i in range(3):
    t = threading.Thread(target=worker)
    t.start()
    threads.append(t)

# Add items to the queue
for item in range(10):
    q.put(item)

# Block until all tasks are done
q.join()

# Stop workers
for i in range(3):
    q.put(None)
for t in threads:
    t.join()

What does the None in the queue signify?

The None is a signal to the worker threads that they should stop processing. When a thread retrieves None, it breaks out of the loop and terminates.