code: def test_simple_vertical_split_exception_on_bad_param(self):
      # bad value for vertical_split_type
      with pytest.raises(AttributeError):
          train_set, test_set = train_test_split(
              make_dataset(4, 10),
              axis=1,
              vertical_split_type="WRONG_VALUE",
              test_size=2,
          )
  
imports: import pytest
  from darts.utils.model_selection import MODEL_AWARE, SIMPLE, train_test_split
  from darts.utils.timeseries_generation import constant_timeseries
label_desc: Use image node_id 23 for calling the TestClassTrainTestSplit obj's underlying member method code with example usage: obj.test_simple_vertical_split_exception_on_bad_param() without return types