Hello

In the age of passwords getting stolen or "hacked", I think it is OK to implement 2FA and FIDO to this library. I am hoping it is not too much work:

• Optional[str] field on the User model for the private key
• The login included the 2FA or FIDO key.
• Authentication based on None (existing way), 2FA, or FIDO

I'd love to hear your opinion on this matter.

Thank you
Can