Changing password length requirement

How do I modify this from the 7 character default on TLJH? On my environment the users are created by the admin but allowed users to create their passwords the first they logged in.

edit: I was able to add the following to the config.yaml and it works. Anybody know how I can enforce password complexity?

type: firstuseauthenticator.FirstUseAuthenticator
min_password_length: 10