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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _make_user_model(self):
 """ 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. """

        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