code: def test_kubernetes(self, mock_kubernetes, mock_hvac):
      mock_client = mock.MagicMock()
      mock_hvac.Client.return_value = mock_client
      vault_client = _VaultClient(
          auth_type="kubernetes",
          kubernetes_role="kube_role",
          kubernetes_jwt_path="path",
          url="http://localhost:8180",
          session=None,
      )
      with patch(
          "builtins.open", mock_open(read_data="data")
      ) as mock_file:
          client = vault_client.client
      mock_file.assert_called_with("path")
      mock_hvac.Client.assert_called_with(
          url="http://localhost:8180", session=None
      )
      mock_kubernetes.assert_called_with(mock_client.adapter)
      mock_kubernetes.return_value.login.assert_called_with(
          role="kube_role", jwt="data"
      )
      client.is_authenticated.assert_called_with()
      assert 2 == vault_client.kv_engine_version
  
imports: from __future__ import annotations
  from unittest import mock
  from unittest.mock import mock_open, patch
  import pytest
  from hvac.exceptions import InvalidPath, VaultError
  from requests import Session
  from requests.adapters import HTTPAdapter
  from urllib3.util import Retry
  from airflow.providers.hashicorp._internal_client.vault_client import _VaultClient
label_desc: Use image node_id 21 for calling the TestVaultClient obj's underlying member method code with example usage: obj.test_kubernetes(mock_kubernetes, mock_hvac) without return types