code: def test_permitted_param_periods(_periods):
      transformer = ExpandingWindowFeatures(periods=_periods)
      assert transformer.periods == _periods
  
file_path: feature_engine/tests/test_time_series/test_forecasting/test_expanding_window_features.py
imports: import numpy
  import pytest
  from pandas.testing import assert_frame_equal
  from feature_engine.timeseries.forecasting import ExpandingWindowFeatures
label_desc: Use image node_id 3 for calling a global function with example usage: test_permitted_param_periods(_periods) without return types