code: def __enter__(self) -> "ManagedSlurmCluster":
      self._start_devcluster()
      return self
  
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 2 for calling the ManagedSlurmCluster obj's underlying member method code with example usage: obj.__enter__() and returns: self