@classmethod
@db.transactional
def mark_running(cls, ticket, worker_id):
    task = cls._get_or_raise_not_found_error(ticket)
    task.status = _ExternalTask.RUNNING
    task.worker_id = worker_id
    db.put(task)
@classmethod
@db.transactional
def mark_running(cls, ticket, worker_id):
    task = cls._get_or_raise_not_found_error(ticket)
    task.status = _ExternalTask.RUNNING
    task.worker_id = worker_id
    db.put(task)