code: def test_infer_relative_search_space_1d() -> None:
      sampler = optuna.integration.PyCmaSampler()
      study = optuna.create_study(sampler=sampler)
  
      # The distribution has only one candidate.
      study.optimize(lambda t: t.suggest_int("x", 1, 1), n_trials=1)
      assert (
          sampler.infer_relative_search_space(study, study.best_trial)
          == {}
      )
  
imports: import math
  from typing import Any
  from typing import Dict
  from unittest.mock import call
  from unittest.mock import patch
  import warnings
  import _pytest.capture
  import pytest
  import optuna
  from optuna._imports import try_import
  from optuna.distributions import BaseDistribution
  from optuna.distributions import CategoricalDistribution
  from optuna.distributions import FloatDistribution
  from optuna.distributions import IntDistribution
  from optuna.integration.cma import _Optimizer
  from optuna.study._study_direction import StudyDirection
  from optuna.testing.distributions import UnsupportedDistribution
  from optuna.testing.trials import _create_frozen_trial
  from optuna.trial import Trial
  from optuna.trial import TrialState
label_desc: Use image node_id 4 for calling the TestPyCmaSampler obj's underlying member method code with example usage: obj.test_infer_relative_search_space_1d() without return types