code: def test_is_ray_running_reachable(self):
      all_status = set(Instance.InstanceStatus.values())
      instance = InstanceUtil.new_instance("i-123", "type_1", "rq-1")
      positive_status = {
          Instance.QUEUED,
          Instance.REQUESTED,
          Instance.ALLOCATED,
          Instance.RAY_INSTALLING,
          Instance.ALLOCATION_FAILED,
      }
      for s in positive_status:
          instance.status = s
          assert InstanceUtil.is_ray_running_reachable(instance)
          assert exists_path(
              s,
              Instance.RAY_RUNNING,
              InstanceUtil.get_valid_transitions(),
          )
          all_status.remove(s)
  
      # Unknown not possible.
      all_status.remove(Instance.UNKNOWN)
      for s in all_status:
          instance.status = s
          assert not InstanceUtil.is_ray_running_reachable(instance)
          assert not exists_path(
              s,
              Instance.RAY_RUNNING,
              InstanceUtil.get_valid_transitions(),
          )
  
file_path: ray/python/ray/autoscaler/v2/tests/test_instance_manager.py
imports: import os
  import sys
  import unittest
  from typing import Dict, Set
  from unittest.mock import patch
  import pytest
  from ray.autoscaler.v2.instance_manager.instance_manager import InstanceUtil
  from ray.autoscaler.v2.schema import InvalidInstanceStatusError
  from ray.core.generated.instance_manager_pb2 import Instance
label_desc: Use image node_id 5 for calling the InstanceUtilTest obj's underlying member method code with example usage: obj.test_is_ray_running_reachable() without return types