python

TypeVar bound to non-class type

TypeError.*TypeVar.*bound.*is not a class

Fixes

1.Use a Protocol class as the bound instead
2.Ensure the bound argument is a concrete class or Protocol
3.Use constraints parameter instead of bound for union-like behavior

pythontypingtypevar

Related Errors

Asyncio event loop already running

RuntimeError: This event loop is already running

•Use nest_asyncio.apply() to allow nested event loops
•Use asyncio.run_coroutine_threadsafe() instead of asyncio.run()

Coroutine never awaited

RuntimeWarning: coroutine '.*' was never awaited

•Add 'await' before the coroutine call
•Use asyncio.create_task() to schedule the coroutine

Asyncio task was cancelled

asyncio\.CancelledError

•Handle CancelledError in try/except within the task
•Use asyncio.shield() to protect critical sections from cancellation