code: def test_difference_name_preservation(
      self, index, second_name, expected, sort
  ):
      first = index[5:20]
      second = index[:10]
      answer = index[10:20]
  
      first.name = "name"
      second.name = second_name
      result = first.difference(second, sort=sort)
  
      if sort is True:
          tm.assert_index_equal(result, answer)
      else:
          answer.name = second_name
          tm.assert_index_equal(
              result.sort_values(), answer.sort_values()
          )
  
      if expected is None:
          assert result.name is None
      else:
          assert result.name == expected
  
imports: from datetime import datetime
  import operator
  import numpy
  import pytest
  from pandas._libs import lib
  from pandas.core.dtypes.cast import find_common_type
  from pandas import CategoricalDtype, CategoricalIndex, DatetimeTZDtype, Index, MultiIndex, PeriodDtype, RangeIndex, Series, Timestamp
  import pandas._testing
  from pandas.api.types import is_signed_integer_dtype, pandas_dtype
label_desc: Use image node_id 9 for calling the TestSetOpsUnsorted obj's underlying member method code with example usage: obj.test_difference_name_preservation(index, second_name, expected, sort) without return types