code: def test_HierarchicalValidation(self) -> None:
      self.assertFalse(self.param1.is_hierarchical)
      with self.assertRaises(NotImplementedError):
          self.param1.dependents
      with self.assertRaises(UserInputError):
          ChoiceParameter(
              name="x",
              parameter_type=ParameterType.BOOL,
              values=[True, False],
              # pyre-fixme[6]: For 4th param expected `Optional[Dict[Union[None,
              #  bool, float, int, str], List[str]]]` but got `Dict[str, str]`.
              dependents={"not_a_value": "other_param"},
          )
      # Check that empty dependents doesn't flag as hierarchical.
      self.param4._dependents = {}
      self.assertFalse(self.param4.is_hierarchical)
      # Check that valid dependents are detected.
      self.param4._dependents = {1: ["other_param"]}
      self.assertTrue(self.param4.is_hierarchical)
  
imports: from ax.core.parameter import _get_parameter_type, ChoiceParameter, EPS, FixedParameter, ParameterType, RangeParameter
  from ax.exceptions.core import UserInputError
  from ax.utils.common.testutils import TestCase
  from ax.utils.common.typeutils import not_none
label_desc: Use image node_id 10 for calling the ChoiceParameterTest obj's underlying member method code with example usage: obj.test_HierarchicalValidation() without return types