text: 
  class AdminAuthenticationProvider(object):
      def __init__(self, integration):
          self.integration = integration
  
      def sign_in_template(self, redirect_url):
          # Returns HTML to be rendered on the sign in page for
          # this authentication provider.
          raise NotImplementedError()
  
      def active_credentials(self, admin):
          # Returns True if the admin's credentials are not expired.
          raise NotImplementedError()
  