The error “Task exception was never retrieved” in Python’s asyncio module usually occurs when an exception is raised within a task and it is not caught within the task. This can happen if the task raises an exception and there is no try-except block to catch the exception within the task’s code. To fix this error, you can either add a try-except block in the task to catch and handle any exceptions that may be raised, or you can retrieve the exception using the
Task.exception() method after the task has completed. Here’s an example of how you can use the
Task.exception() method to retrieve the exception:
import asyncio async def my_task(): # code that may raise an exception loop = asyncio.get_event_loop() task = loop.create_task(my_task()) # Wait for the task to complete await task # Check if the task raised an exception if task.exception(): # Handle the exception print(task.exception())
You can also use the
asyncio.gather() function to run multiple tasks concurrently and retrieve any exceptions that may be raised by the tasks.
import asyncio async def my_task1(): # code that may raise an exception async def my_task2(): # code that may raise an exception loop = asyncio.get_event_loop() # Run the tasks concurrently and retrieve any exceptions results = await asyncio.gather(my_task1(), my_task2()) # Check if any of the tasks raised an exception for result in results: if isinstance(result, Exception): # Handle the exception print(result)