def METHOD_NAME(self):
    worker_process = []
    for i in range(self.worker_num):
        worker_task_spec = {
            "task": {
                "type": "worker",
                "index": i,
            }
        }
        p = self.update_spec_and_start_process(worker_task_spec)
        worker_process.append(p)
    return worker_process