    def progress_url(self, server_name=''):
        """API URL for progress endpoint for a server with a given name"""
        url_parts = [self.settings['hub'].base_url, 'api/users', self.escaped_name]
        if server_name:
            url_parts.extend(['servers', url_escape_path(server_name), 'progress'])
        else:
            url_parts.extend(['server/progress'])
        return url_path_join(*url_parts)
API URL for progress endpoint for a server with a given name
jupyterhub/user.py