code: def test_split_object_mixed(expand, method):
      mixed = Series(
          [
              "a_b_c",
              np.nan,
              "d_e_f",
              True,
              datetime.today(),
              None,
              1,
              2.0,
          ]
      )
      result = getattr(mixed.str, method)("_", expand=expand)
      exp = Series(
          [
              ["a", "b", "c"],
              np.nan,
              ["d", "e", "f"],
              np.nan,
              np.nan,
              None,
              np.nan,
              np.nan,
          ]
      )
      assert isinstance(result, Series)
      tm.assert_almost_equal(result, exp)
  
imports: from datetime import datetime
  import re
  import numpy
  import pytest
  import pandas
  from pandas import DataFrame, Index, MultiIndex, Series, _testing
  from pandas.tests.strings import _convert_na_value, object_pyarrow_numpy
label_desc: Use image node_id 6 for calling a global function with example usage: test_split_object_mixed(expand, method) without return types