code: def test_getitem_datetime_slice(self):
      # GH#43223
      df = DataFrame(
          {"a": 0},
          index=DatetimeIndex(
              [
                  "11.01.2011 22:00",
                  "11.01.2011 23:00",
                  "12.01.2011 00:00",
                  "2011-01-13 00:00",
              ]
          ),
      )
      with pytest.raises(
          KeyError, match="Value based partial slicing on non-monotonic"
      ):
          df["2011-01-01":"2011-11-01"]
  
imports: import re
  import numpy
  import pytest
  from pandas import Categorical, CategoricalDtype, CategoricalIndex, DataFrame, DateOffset, DatetimeIndex, Index, MultiIndex, Series, Timestamp, concat, date_range, get_dummies, period_range
  import pandas._testing
  from pandas.core.arrays import SparseArray
label_desc: Use image node_id 2 for calling the TestGetitemSlice obj's underlying member method code with example usage: obj.test_getitem_datetime_slice() without return types