[Python] Python async sleep question ordering of execution

Hello I have a quesiton while I'm working through some tutorial on asyncio as given below:

import asyncio
async def task_coroutine():
print('start executing task')
await asyncio.sleep(1.0)
print('done waiting in task')
raise Exception('error in task')
return 99

async def main():
print('main started')
task = asyncio.create_task(task_coroutine())
await asyncio.sleep(1.1)
print('done waiting in main')
try:
value = task.result()
except Exception as e:
print(e)
print('end of main')
asyncio.run(main())



as I expected, the result is

main started
start executing task
done waiting in task
done waiting in main
error in task
end of main


because when the task suspend, the main is still sleeping and it switches back to task to throw.

I have been playing around a bit by changing the sleep time of main to 0.1 (1.1 before) and the result is also as I expected

main started
start executing task
done waiting in main
Result is not set.
end of main


since the main trying to collect result of task before it's done so it throws "Result is not set"

However, when I set the sleep time of main to 1.0000000001, it gives:

main started
start executing task
done waiting in main
Result is not set.
end of main
done waiting in task

Task exception was never retrieved
future: <Task finished name='Task-2' coro=<task_coroutine() done, defined at /Users/user/Library/Application Support/JetBrains/PyCharm2024.1/scratches/scratch.py:3> exception=Exception('error in task')>
Traceback (most recent call last):
File "/Users/charlielao/Library/Application Support/JetBrains/PyCharm2024.1/scratches/scratch.py", line 7, in task_coroutine
raise Exception('error in task')
Exception: error in task


I don't quite understand why it prints "done waiting in task" at the end after main finishes where it didn't in the 0.1 case, why is there explicit error in this case, what was the exact ordering of events?

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