code: def ensure_agent_ok(self) -> None:
      pass
  
imports: import os
  import subprocess
  import time
  from shlex import split
  from typing import Any, Iterator
  import pytest
  from tests import config
  from .abstract_cluster import Cluster
  from .utils import now_ts
label_desc: Use image node_id 7 for calling the ManagedSlurmCluster obj's underlying member method code with example usage: obj.ensure_agent_ok() without return types