I have two files 'main.py' and 'keep_alive.py'. I am trying to run selenium in the main file and in other threads I am trying to run keep_alive.py which creates a flask webserver so that I can ping the keep_alive server with uptimerobot. So that both the file will run in repl.it servers 24/7. But when selenium starts the flask webserver stops running and ti shows an error

handler = _signal.signal(_enum_to_int(signalnum), _enum_to_int(handler))
ValueError: signal only works in main thread