code: def test_propagation_two():
      """[Parallel] Test feature propagation from original data to second layer"""
      # Check that original data is propagated through second layer
      out_2 = ens2.fit(X, y, return_preds=True)
      np.testing.assert_array_equal(
          out_2[:, :n_first_prop], X[:, first_prop]
      )
  
file_path: mlens/mlens/parallel/tests/test_c_multi_sparse_feature_prop.py
imports: import numpy
  from scipy.sparse import csr_matrix
  from mlens.index import FoldIndex
  from mlens.ensemble.base import BaseEnsemble
  from mlens.externals.sklearn.validation import check_random_state
  from mlens.utils.dummy import OLS
label_desc: Use image node_id 3 for calling a global function with example usage: test_propagation_two() without return types