code: def test_TransformObservationFeatures(self) -> None:
      obs_ft1 = deepcopy(self.training_feats)
      obs_ft2 = deepcopy(self.training_feats)
      obs_ft_trans1 = [
          ObservationFeatures({"x": 1, "TRIAL_PARAM": "0"}),
          ObservationFeatures({"x": 2, "TRIAL_PARAM": "0"}),
          ObservationFeatures({"x": 3, "TRIAL_PARAM": "1"}),
          ObservationFeatures({"x": 4, "TRIAL_PARAM": "2"}),
      ]
      obs_ft_trans2 = [
          ObservationFeatures({"x": 1, "bp1": "v1", "bp2": "u1"}),
          ObservationFeatures({"x": 2, "bp1": "v1", "bp2": "u1"}),
          ObservationFeatures({"x": 3, "bp1": "v2", "bp2": "u1"}),
          ObservationFeatures({"x": 4, "bp1": "v3", "bp2": "u2"}),
      ]
      obs_ft1 = self.t.transform_observation_features(obs_ft1)
      self.assertEqual(obs_ft1, obs_ft_trans1)
      obs_ft2 = self.t2.transform_observation_features(obs_ft2)
      self.assertEqual(obs_ft2, obs_ft_trans2)
      obs_ft1 = self.t.untransform_observation_features(obs_ft1)
      self.assertEqual(obs_ft1, self.training_feats)
      obs_ft3 = self.t2.transform_observation_features(
          [ObservationFeatures({})]
      )
      self.assertEqual(obs_ft3[0], ObservationFeatures({}))
      obs_ft4 = deepcopy(self.training_feats)
      obs_ft4 = self.t3.untransform_observation_features(obs_ft4)
      self.assertEqual(obs_ft4, self.training_feats)
  
file_path: Ax/ax/modelbridge/transforms/tests/test_trial_as_task_transform.py
imports: from copy import deepcopy
  import numpy
  from ax.core.observation import Observation, ObservationData, ObservationFeatures
  from ax.core.parameter import ChoiceParameter, ParameterType, RangeParameter
  from ax.core.search_space import SearchSpace
  from ax.exceptions.core import UnsupportedError
  from ax.modelbridge.transforms.trial_as_task import TrialAsTask
  from ax.utils.common.testutils import TestCase
  from ax.utils.testing.core_stubs import get_robust_search_space
label_desc: Use image node_id 3 for calling the TrialAsTaskTransformTest obj's underlying member method code with example usage: obj.test_TransformObservationFeatures() without return types