code: def test_get_variable_value_without_predefined_mount_point(
      self, mock_hvac
  ):
      mock_client = mock.MagicMock()
      mock_hvac.Client.return_value = mock_client
      mock_client.secrets.kv.v2.read_secret_version.return_value = {
          "request_id": "2d48a2ad-6bcb-e5b6-429d-da35fdf31f56",
          "lease_id": "",
          "renewable": False,
          "lease_duration": 0,
          "data": {
              "data": {"value": "world"},
              "metadata": {
                  "created_time": "2020-03-28T02:10:54.301784Z",
                  "deletion_time": "",
                  "destroyed": False,
                  "version": 1,
              },
          },
          "wrap_info": None,
          "warnings": None,
          "auth": None,
      }
  
      kwargs = {
          "variables_path": "variables",
          "mount_point": None,
          "auth_type": "token",
          "url": "http://127.0.0.1:8200",
          "token": "s.7AU0I51yv1Q1lxOIg1F3ZRAS",
      }
  
      test_client = VaultBackend(**kwargs)
      returned_uri = test_client.get_variable("airflow/hello")
      assert "world" == returned_uri
  
imports: from __future__ import annotations
  from unittest import mock
  import pytest
  from hvac.exceptions import InvalidPath, VaultError
  from airflow.providers.hashicorp.secrets.vault import VaultBackend
label_desc: Use image node_id 9 for calling the TestVaultSecrets obj's underlying member method code with example usage: obj.test_get_variable_value_without_predefined_mount_point(mock_hvac) without return types