class_docstr: `FeatureConnector` for integer class labels.
code: def names(self) -> Optional[list[str]]:
      if not self._int2str:
          return [str(i) for i in range(self._num_classes)]
      return list(self._int2str)
  
imports: from typing import Optional, Union
  from etils import epath
  import numpy
  from tensorflow_datasets.core.features import feature
  from tensorflow_datasets.core.features import tensor_feature
  from tensorflow_datasets.core.proto import feature_pb2
  from tensorflow_datasets.core.utils import type_utils
label_desc: Use image node_id 3 for calling the ClassLabel obj's underlying member method code with example usage: obj.names() and returns: list, unknown