class_docstr: everything you wanted to test about sorting
class_docstr_tok: ["everything","you","wanted","to","test","about","sorting"]
code: def test_sort_non_lexsorted(self):
      # degenerate case where we sort but don't
      # have a satisfying result :<
      # GH 15797
      idx = MultiIndex(
          [["A", "B", "C"], ["c", "b", "a"]],
          [[0, 1, 2, 0, 1, 2], [0, 2, 1, 1, 0, 2]],
      )
  
      df = DataFrame({"col": range(len(idx))}, index=idx, dtype="int64")
      assert df.index.is_monotonic_increasing is False
  
      sorted = df.sort_index()
      assert sorted.index.is_monotonic_increasing is True
  
      expected = DataFrame(
          {"col": [1, 4, 5, 2]},
          index=MultiIndex.from_tuples(
              [("B", "a"), ("B", "c"), ("C", "a"), ("C", "b")]
          ),
          dtype="int64",
      )
      result = sorted.loc[pd.IndexSlice["B":"C", "a":"c"], :]
      tm.assert_frame_equal(result, expected)
  
imports: import datetime
  import numpy
  import pytest
  import pandas
  from pandas import DataFrame, MultiIndex, Series
  import pandas._testing
label_desc: Use image node_id 1 for calling the TestSorted obj's underlying member method code with example usage: obj.test_sort_non_lexsorted() without return types