code: def test_list_eval_all_null() -> None:
      df = pl.DataFrame(
          {"foo": [1, 2, 3], "bar": [None, None, None]}
      ).with_columns(pl.col("bar").cast(pl.List(pl.String)))
  
      assert df.select(pl.col("bar").list.eval(pl.element())).to_dict(
          as_series=False
      ) == {"bar": [None, None, None]}
  
imports: from __future__ import annotations
  from datetime import date, datetime
  import numpy
  import pytest
  import polars
  from polars.testing import assert_frame_equal, assert_series_equal
label_desc: Use image node_id 22 for calling a global function with example usage: test_list_eval_all_null() without return types