code: def test_annotations_slices():
      """Test indexing Annotations."""
      NUM_ANNOT = 5
      EXPECTED_ONSETS = EXPECTED_DURATIONS = [
          x for x in range(NUM_ANNOT)
      ]
      EXPECTED_DESCS = [x.__repr__() for x in range(NUM_ANNOT)]
  
      annot = Annotations(
          onset=EXPECTED_ONSETS,
          duration=EXPECTED_DURATIONS,
          description=EXPECTED_DESCS,
          orig_time=None,
      )
  
      # Indexing returns a copy. So this has no effect in annot
      annot[0]["onset"] = 42
      annot[0]["duration"] = 3.14
      annot[0]["description"] = "foobar"
  
      annot[:1].onset[0] = 42
      annot[:1].duration[0] = 3.14
      annot[:1].description[0] = "foobar"
  
      # Slicing with single element returns a dictionary
      for ii in EXPECTED_ONSETS:
          assert annot[ii] == dict(
              zip(
                  ["onset", "duration", "description", "orig_time"],
                  [ii, ii, str(ii), None],
              )
          )
  
      # Slices should give back Annotations
      for current in (
          annot[slice(0, None, 2)],
          annot[[bool(ii % 2) for ii in range(len(annot))]],
          annot[:1],
          annot[[0, 2, 2]],
          annot[(0, 2, 2)],
          annot[np.array([0, 2, 2])],
          annot[1::2],
      ):
          assert isinstance(current, Annotations)
          assert len(current) != len(annot)
  
      for bad_ii in [len(EXPECTED_ONSETS), 42, "foo"]:
          with pytest.raises(IndexError):
              annot[bad_ii]
  
imports: import sys
  from collections import OrderedDict
  from datetime import datetime, timedelta, timezone
  from itertools import repeat
  from pathlib import Path
  import numpy
  import pytest
  from numpy.testing import assert_allclose, assert_array_almost_equal, assert_array_equal, assert_equal
  from pytest import approx
  import mne
  from mne import Annotations, Epochs, annotations_from_events, count_annotations, create_info, events_from_annotations, read_annotations
  from mne.annotations import _handle_meas_date, _read_annotations_txt_parse_header, _sync_onset
  from mne.datasets import testing
  from mne.io import RawArray, concatenate_raws, read_raw_fif
  from mne.utils import _dt_to_stamp, _raw_annot, _record_warnings, _stamp_to_dt, assert_and_remove_boundary_annot, catch_logging, check_version
label_desc: Use image node_id 33 for calling a global function with example usage: test_annotations_slices() without return types