def __verify_hackathon(self, hackathon_name):
        """validate the event_start_time and event_end_time of a hackathon

        Will return None if hackathon not found or current time is not between its start time and end time
        """
        hackathon = self.hackathon_manager.get_hackathon_by_name(hackathon_name)
        if hackathon:
            if HACKATHON_CONFIG.CLOUD_PROVIDER not in hackathon.config:
                raise PreconditionFailed("No cloud resource is configured for this hackathon.")
            if self.util.get_now() < hackathon.event_end_time:
                return hackathon
            else:
                raise PreconditionFailed("Hackathon was already ended")
        else:
            raise NotFound("Hackathon with name %s not found" + hackathon_name)
dataset/ETHPy150Open msopentechcn/open-hackathon/open-hackathon-server/src/hackathon/expr/expr_mgr.py/ExprManager.__verify_hackathon/operator `%` -> `+`