code: def test_returns_helper(self) -> None:
      with mock.patch(
          "bokeh.util.version._base_version_helper"
      ) as helper:
          buv.base_version()
          assert helper.called
  
file_path: bokeh/tests/unit/bokeh/util/test_version.py
imports: from __future__ import annotations
  import pytest
  import re
  from unittest import mock
  import bokeh.util.version
label_desc: Use image node_id 1 for calling the Test_base_version obj's underlying member method code with example usage: obj.test_returns_helper() without return types