    def find_group(self, group_name):
        """Find and return a group by name.

        Raise 404 if not found.
        """
        group = orm.Group.find(self.db, name=group_name)
        if group is None:
            raise web.HTTPError(404, "No such group: %s", group_name)
        return group
Find and return a group by name.

Raise 404 if not found.
jupyterhub/apihandlers/groups.py