code: def test_rolling_map_np_nansum() -> None:
      s = pl.Series("a", [11.0, 2.0, 9.0, float("nan"), 8.0])
  
      result = s.rolling_map(np.nansum, 3)
  
      expected = pl.Series("a", [None, None, 22.0, 11.0, 17.0])
      assert_series_equal(result, expected)
  
file_path: polars/py-polars/tests/unit/operations/rolling/test_map.py
imports: from __future__ import annotations
  import numpy
  import pytest
  import polars
  from polars.testing import assert_series_equal
label_desc: Use image node_id 3 for calling a global function with example usage: test_rolling_map_np_nansum() without return types