code: def _download_ann(self):
      pass
  
file_path: lavis/lavis/datasets/builders/imagefolder_builder.py
imports: import os
  from lavis.common.registry import registry
  from lavis.datasets.builders.base_dataset_builder import BaseDatasetBuilder
  from lavis.datasets.datasets.imagefolder_dataset import ImageFolderDataset
label_desc: Use image node_id 1 for calling the ImageNetBuilder obj's underlying member method code with example usage: obj._download_ann() without return types