code: def test_indexsubset_indextreatment(index_treatment):
      """Test that index_treatment behaviour in IndexSubsetworks as intended."""
      X = load_airline()[0:32]
      y = load_airline()[24:42]
      transformer = IndexSubset(index_treatment=index_treatment)
      X_subset = transformer.fit_transform(X=X, y=y)
      if index_treatment == "remove":
          assert X_subset.index.equals(X.index.intersection(y.index))
      elif index_treatment == "keep":
          assert X_subset.index.equals(y.index)
  
file_path: sktime/sktime/transformations/series/tests/test_subset.py
imports: import pandas
  import pytest
  from sktime.datasets import load_airline, load_longley
  from sktime.forecasting.naive import NaiveForecaster
  from sktime.transformations.series.subset import ColumnSelect, IndexSubset
label_desc: Use image node_id 1 for calling a global function with example usage: test_indexsubset_indextreatment(index_treatment) without return types