code: def custom_auth(principal, credentials, realm, scheme, **parameters):
      
      from neobolt.security import AuthToken
      return AuthToken(scheme, principal, credentials, realm, **parameters)
docs: Generate a basic auth token for a given user and password.
  
      :param principal: specifies who is being authenticated
      :param credentials: authenticates the principal
      :param realm: specifies the authentication provider
      :param scheme: specifies the type of authentication
      :param parameters: parameters passed along to the authentication provider
      :return: auth token for use with :meth:`GraphDatabase.driver`