pythoncode.club uses OAuth2 to verify that you are a real person and that you have the right to access a pythoncode.club account. We just communicate with the OAuth2 provider during the login or signup step.
OAuth2 is a standard for verifying that you have a particular account with another provider. We just do the authentication with the help of the providers above and don't share any other information with them. We also try to fetch as little information as possible about you from the providers above. You can read more about OAuth2 on this Wikipedia page.