code: def test_split_blank_string(any_string_dtype):
      # expand blank split GH 20067
      values = Series([""], name="test", dtype=any_string_dtype)
      result = values.str.split(expand=True)
      exp = DataFrame(
          [[]], dtype=any_string_dtype
      )  # NOTE: this is NOT an empty df
      tm.assert_frame_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 10 for calling a global function with example usage: test_split_blank_string(any_string_dtype) without return types