code: def setUp(self) -> None:
      self.obsd1 = ObservationData(
          metric_names=["m1", "m2", "m2"],
          means=np.array([1.0, 2.0, 8.0]),
          covariance=np.array(
              [[1.0, 0.2, 0.4], [0.2, 2.0, 0.8], [0.4, 0.8, 3.0]]
          ),
      )
      self.obsd2 = ObservationData(
          metric_names=["m1", "m1", "m2", "m2"],
          means=np.array([1.0, 5.0, 2.0, 1.0]),
          covariance=np.array(
              [
                  [1.0, 0.0, 0.0, 0.0],
                  [0.0, 1.0, 0.2, 0.4],
                  [0.0, 0.2, 2.0, 0.8],
                  [0.0, 0.4, 0.8, 3.0],
              ]
          ),
      )
      self.search_space = SearchSpace(
          parameters=[
              RangeParameter(
                  name="x",
                  parameter_type=ParameterType.FLOAT,
                  lower=0,
                  upper=10,
              ),
              ChoiceParameter(
                  name="z",
                  parameter_type=ParameterType.STRING,
                  values=["a", "b"],
              ),
          ]
      )
      self.obsf1 = ObservationFeatures({"x": 2, "z": "a"})
      self.obsf2 = ObservationFeatures({"x": 5, "z": "b"})
      self.obs1 = Observation(features=self.obsf1, data=self.obsd1)
      self.obs2 = Observation(features=self.obsf2, data=self.obsd2)
      self.t = StratifiedStandardizeY(
          search_space=self.search_space,
          observations=[self.obs1, self.obs2],
          config={"parameter_name": "z"},
      )
  
imports: from copy import deepcopy
  from math import sqrt
  import numpy
  from ax.core.metric import Metric
  from ax.core.objective import Objective
  from ax.core.observation import Observation, ObservationData, ObservationFeatures
  from ax.core.optimization_config import OptimizationConfig
  from ax.core.outcome_constraint import OutcomeConstraint
  from ax.core.parameter import ChoiceParameter, ParameterType, RangeParameter
  from ax.core.search_space import SearchSpace
  from ax.core.types import ComparisonOp
  from ax.modelbridge.transforms.stratified_standardize_y import StratifiedStandardizeY
  from ax.modelbridge.transforms.tests.test_standardize_y_transform import osd_allclose
  from ax.utils.common.testutils import TestCase
label_desc: Use image node_id 1 for calling the StratifiedStandardizeYTransformTest obj's underlying member method code with example usage: obj.setUp() without return types