code: def test_cmov_window_regular_linear_range(win_types, step):
      # GH 8238
      pytest.importorskip("scipy")
      vals = np.array(range(10), dtype=float)
      rs = (
          Series(vals)
          .rolling(5, win_type=win_types, center=True, step=step)
          .mean()
      )
      xp = vals
      xp[:2] = np.nan
      xp[-2:] = np.nan
      xp = Series(xp)[::step]
  
      tm.assert_series_equal(xp, rs)
  
imports: import numpy
  import pytest
  from pandas import DataFrame, Series, Timedelta, concat, date_range
  import pandas._testing
  from pandas.api.indexers import BaseIndexer
label_desc: Use image node_id 21 for calling a global function with example usage: test_cmov_window_regular_linear_range(win_types, step) without return types