When to use asyncio.gather, and when TaskGroup? Pros and cons of each.

asyncio.gather and asyncio.TaskGroup are both used to run multiple coroutines concurrently but have different scenarios and features.

asyncio.gather:

• Runs multiple coroutines and collects their results.
• If one coroutine raises an exception, gather by default cancels the others and raises the exception.
• Can be used with the parameter return_exceptions=True to collect all exceptions as results.
• Suitable when you need to get results from all tasks and process them together.

asyncio.TaskGroup (Python 3.11+):

• A context manager for grouping tasks.
• Allows creating tasks within a block, automatically waiting for their completion.
• Cancels remaining tasks if one task raises an exception.
• More convenient for structuring code and managing task lifecycle.

Pros and cons:

Feature	asyncio.gather	asyncio.TaskGroup
Python version	3.7+	3.11+
Task management	Explicit creation and collection	Automatic management
Exception handling	Can collect all exceptions	Cancels all on exception
Code readability	Less structured	More structured code

When to use:

• If compatibility with Python versions below 3.11 is needed — asyncio.gather.
• If structured code and automatic task management are important — TaskGroup.

Example with TaskGroup:

import asyncio

async def worker(n):
    await asyncio.sleep(n)
    return n

async def main():
    async with asyncio.TaskGroup() as tg:
        tg.create_task(worker(1))
        tg.create_task(worker(2))
    print("All tasks completed")

asyncio.run(main())