code: def __init__(
      self, benchmark: GenericCLScenario, stream: str = "train"
  ):
      self._benchmark = benchmark
      self._stream = stream
  
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 1 to create a new _LazyClassesInClassificationExps object from inherited base classes: Sequence with example: obj = _LazyClassesInClassificationExps(benchmark, stream)