OAuthlib (Django OAuth Toolkit, if you are willing to use Django) &
I advise you to check also some of OAuth2.0 libraries for implementing an OAuth2.0 authorization server, such as oauth2orize (with oauth2orize-openid) and node-oauth20-provider. Remember that OpenID Connect (OIDC) is a thin layer on top of the OAuth2.0 protocol
I recommend you visiting: https://openid.net/developers/certified/, for finding Certified OpenID Connect Providers for every coding language!
I hope that helps, please let me know if you have any more questions