code: def test_permitted_param_sort_index(_sort_index):
      transformer = LagFeatures(sort_index=_sort_index)
      assert transformer.sort_index == _sort_index
  
file_path: feature_engine/tests/test_time_series/test_forecasting/test_lag_features.py
imports: import numpy
  import pandas
  import pytest
  from feature_engine.timeseries.forecasting import LagFeatures
label_desc: Use image node_id 4 for calling a global function with example usage: test_permitted_param_sort_index(_sort_index) without return types