code: def __getitem__(self, stream_name_or_exp_id):
      if isinstance(stream_name_or_exp_id, str):
          return _LazyClassesInClassificationExps(
              self._benchmark, stream=stream_name_or_exp_id
          )
  
      warnings.warn(
          "Using classes_in_experience[exp_id] is deprecated. "
          "Consider using classes_in_experience[stream_name][exp_id]"
          "instead.",
          stacklevel=2,
      )
      return self._default_lcie[stream_name_or_exp_id]
  
imports: from typing import Callable, TypeVar, Union, Sequence, Optional, Iterable, List, Set, Tuple, Mapping, overload, TYPE_CHECKING
  import warnings
  from avalanche.benchmarks.scenarios.deprecated import AbstractClassTimelineExperience
  from avalanche.benchmarks.scenarios.deprecated.dataset_scenario import ClassesTimelineCLScenario, FactoryBasedStream, TStreamsUserDict
  from avalanche.benchmarks.utils.dataset_utils import manage_advanced_indexing
label_desc: Use image node_id 3 for calling the _LazyStreamClassesInClassificationExps obj's underlying member method code with example usage: obj.__getitem__(stream_name_or_exp_id) and returns: self, _LazyClassesInClassificationExps