def store(self):
        """
        Store a list of resume points to the request's session.
        """
        if self._resume_points:
            self.request.session[self.session_key] = json.dumps(self._resume_points)
        else:
            self.request.session.pop(self.session_key, None)
        return []

        Store a list of resume points to the request's session.
        
resume/middleware.py