Flask SERVER_NAME never correct
I did comment but I managed to reproduce the error exactly in test.
You can not bind to the address example.com and the IP address is not listed on the local machine. I can bind to mydomain.com because it resolves to the address on my server.
Also I think there is a typo in the example i take it you mean host=app.config['SERVER_NAME'] and not have the app missing or the SERVER_NAME in lowercase?
Joe