code: def test_with_use_best_cv_iteration():
      os.environ[
          "sharedtree.crossvalidation.useBestCVIteration"
      ] = "FALSE"
      test_early_stopping_and_cross_validation_correctly_set_actual_params()
      os.environ[
          "sharedtree.crossvalidation.useBestCVIteration"
      ] = "TRUE"
      test_early_stopping_and_cross_validation_correctly_set_actual_params()
  
imports: import sys
  import h2o
  import os
  from tests import pyunit_utils, assert_equals
  from h2o.estimators import H2ORandomForestEstimator, H2OGradientBoostingEstimator, H2OIsolationForestEstimator, H2OXGBoostEstimator
label_desc: Use image node_id 3 for calling a global function with example usage: test_with_use_best_cv_iteration() without return types