Concurrent modification guide with for loops in Python when using threading
I'm collaborating on a project where I'm collaborating on a project where I'm not sure how to approach I'm updating my dependencies and I'm having a hard time understanding This might be a silly question, but I've looked through the documentation and I'm still confused about I'm working with an scenario when trying to modify a list while iterating through it in a separate thread... My goal is to process a list of tasks concurrently, but I'm running into problems with unexpected behavior when I remove items from the list during the loop. The following code demonstrates the scenario: ```python import threading import time class TaskProcessor: def __init__(self, tasks): self.tasks = tasks self.lock = threading.Lock() def process_task(self, task): time.sleep(1) # Simulating a task taking time print(f'Processed: {task}') with self.lock: self.tasks.remove(task) # Removing a task after processing def run(self): for task in list(self.tasks): # Creating a snapshot of the list thread = threading.Thread(target=self.process_task, args=(task,)) thread.start() # Joining threads for thread in threading.enumerate(): if thread is not threading.currentThread(): thread.join() print('Remaining tasks:', self.tasks) if __name__ == '__main__': tasks = ['task1', 'task2', 'task3', 'task4'] processor = TaskProcessor(tasks) processor.run() ``` The expected output should list `Remaining tasks` showing those that weren't processed, but instead, I'm getting an empty list or inconsistent behavior where some tasks seem to skip the processing step entirely. I read that modifying a list while iterating over it can lead to unpredictable behavior. I tried creating a copy of the list to iterate over, but I'm still working with the question. Could someone point out what I'm doing wrong or suggest a better approach? I'm using Python 3.10. For context: I'm using Python on Linux. Any ideas what could be causing this? This is part of a larger web app I'm building. Am I missing something obvious? I'm working on a web app that needs to handle this. Thanks in advance! Is this even possible? I'd love to hear your thoughts on this. Any pointers in the right direction? I recently upgraded to Python 3.10. I recently upgraded to Python 3.10. Could this be a known issue?