code: def test_repr_html_err_nf():
      with mock.patch(
          "tslumen.jinja_utils.create_jinja_env", autospec=True
      ) as jinja:
          env = mock.create_autospec(spec=jinja2.Environment)
          env.get_template.side_effect = lambda *args, **kwargs: (
              _ for _ in ()
          ).throw(jinja2.TemplateNotFound(""))
          jinja.return_value = env
  
          @repr_html
          class Dummy:
              pass
  
          assert getattr(Dummy, "_repr_html_")
          with pytest.warns(
              UserWarning, match=r"could not find jinja template.*"
          ):
              assert isinstance(Dummy()._repr_html_(), str)
  
file_path: tslumen/tests/unit/test_misc.py
imports: import pytest
  import mock
  from inspect import isclass
  import jinja2
  from tslumen.misc import lazyproperty, repr_html, import_error_function, import_error_class, import_error_module
label_desc: Use image node_id 3 for calling a global function with example usage: test_repr_html_err_nf() without return types