code: def _make_user_model(self):
          
          class User(UserBase):
              """
              A User as defined by the response from Keystone.
  
              Note: This class is dynamically generated by :class:`FlaskKeystone`
              from the :class:`flask_keystone.UserBase` class.
  
              :param request: The incoming `flask.Request` object, after being
                              handled by the :mod:`keystonemiddleware`
              :returns: :class:`flask_keystone.UserBase`
              """
              pass
  
          User.generate_has_role_function(self.roles)
          User.generate_is_role_functions(self.roles)
  
          return User
docs: Dynamically generate a User class for use with FlaskKeystone.
  
          :returns: a generated User class, inherited from
                    :class:`flask_keystone.UserBase`.
          :rtype: class
  
          This User model is intended to work somewhat similarly to the User
          class that is created for Flask-Login, however it is Dynamically
          generated based on configuration values in `oslo.config.cfg`, and
          is populated automatically from the request headers added by
          :mod:`keystonemiddleware`.
  
          This User class has the concept of "roles", which are defined in
          oslo.config, and generates helper functions to quickly Determine
          whether these roles apply to a particular instance.