[Number]: Worker started. [number]: Message has read. [number]: Groups has read. [number]: There

Question

[Number]: Worker started. [number]: Message has read. [number]: Groups has read. [number]: There

is no current event loop in thread 'ThreadPoolExecutor-0_0'.

Why do I get such exection when I don't use Teleton's async mode?

I had created and set an event loop by asyncio in each thread, but after some time I was facing the following error:
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RunTimeError: Event loop is closed
RunTimeError: coroutine ignored GeneratorExit
Task was destroyed but it is pending!
Unexpected exception in the send loop
Traceback (most recent call last):
Generator Exit
During handling of the above exception, another exception occurred:
raise RunTimeError('Event loop is closed')
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