code: def test_check_ensemble_build_passes():
      """[Utils] check_ensemble_build : passes on default dummy LC."""
      FLAG = check_ensemble_build(LAYER_CONTAINER)
      assert FLAG is True
  
imports: import numpy
  from mlens.externals.sklearn.base import clone
  from mlens.utils.checks import check_ensemble_build, assert_valid_estimator, assert_correct_format, check_initialized
  from mlens.utils.dummy import OLS, Scale
  from mlens.testing import EstimatorContainer
  from mlens.utils.exceptions import LayerSpecificationError, LayerSpecificationWarning, NotFittedError, ParallelProcessingError, ParallelProcessingWarning
label_desc: Use image node_id 1 for calling a global function with example usage: test_check_ensemble_build_passes() without return types