    async def refresh_user(self, user, handler=None):
        """Refresh auth data for a given user

        Allows refreshing or invalidating auth data.

        Only override if your authenticator needs
        to refresh its data about users once in a while.

        .. versionadded: 1.0

        Args:
            user (User): the user to refresh
            handler (tornado.web.RequestHandler or None): the current request handler
        Returns:
            auth_data (bool or dict):
                Return **True** if auth data for the user is up-to-date
                and no updates are required.

                Return **False** if the user's auth data has expired,
                and they should be required to login again.

                Return a **dict** of auth data if some values should be updated.
                This dict should have the same structure as that returned
                by :meth:`.authenticate()` when it returns a dict.
                Any fields present will refresh the value for the user.
                Any fields not present will be left unchanged.
                This can include updating `.admin` or `.auth_state` fields.
        """
        return True
Refresh auth data for a given user

Allows refreshing or invalidating auth data.

Only override if your authenticator needs
to refresh its data about users once in a while.

.. versionadded: 1.0

Args:
user (User): the user to refresh
handler (tornado.web.RequestHandler or None): the current request handler
Returns:
auth_data (bool or dict):
Return **True** if auth data for the user is up-to-date
and no updates are required.

Return **False** if the user's auth data has expired,
and they should be required to login again.

Return a **dict** of auth data if some values should be updated.
This dict should have the same structure as that returned
by :meth:`.authenticate()` when it returns a dict.
Any fields present will refresh the value for the user.
Any fields not present will be left unchanged.
This can include updating `.admin` or `.auth_state` fields.
jupyterhub/auth.py