code: def test_list_recursive_time_unit_cast() -> None:
      values = [[datetime(2000, 1, 1, 0, 0, 0)]]
      dtype = pl.List(pl.Datetime("ns"))
      s = pl.Series(values)
      out = s.cast(dtype)
      assert out.dtype == dtype
      assert out.to_list() == values
  
imports: from __future__ import annotations
  import pickle
  from datetime import date, datetime, time
  from typing import TYPE_CHECKING, Any
  import pandas
  import pytest
  import polars
  from polars.testing import assert_frame_equal, assert_series_equal
label_desc: Use image node_id 32 for calling a global function with example usage: test_list_recursive_time_unit_cast() without return types