code: def test_selection__tag_exists(mocker: MockerFixture) -> None:
      tag_name = "some-tag"
      mocker.patch.object(
          ApiWorkflowClient, "__init__", return_value=None
      )
      mocker.patch.object(
          ApiWorkflowClient,
          "get_all_tags",
          return_value=_get_tags(
              dataset_id=utils.generate_id(), tag_name=tag_name
          ),
      )
  
      client = ApiWorkflowClient()
      with pytest.raises(RuntimeError) as exception:
          client.selection(
              selection_config=SelectionConfig(name=tag_name)
          )
  
          assert (
              str(exception.value)
              == "There already exists a tag with tag_name some-tag"
          )
  
file_path: lightly/tests/api_workflow/test_api_workflow_selection.py
imports: from typing import List
  import pytest
  from pytest_mock import MockerFixture
  from lightly.active_learning.config.selection_config import SelectionConfig
  from lightly.api import ApiWorkflowClient, api_workflow_selection
  from lightly.openapi_generated.swagger_client.models import JobResultType, JobState, JobStatusData, JobStatusDataResult, SamplingCreateRequest, SamplingMethod, TagData
  from tests.api_workflow import utils
label_desc: Use image node_id 3 for calling a global function with example usage: test_selection__tag_exists(mocker) without return types