code: def get_existing_audio_annotations(self):
      return [f.split("_")[0] for f in os.listdir(self.audio_root)]
  
imports: import os
  from collections import OrderedDict
  from PIL import Image
  import copy
  from lavis.datasets.datasets.base_dataset import BaseDataset
  from lavis.common.utils import is_serializable
label_desc: Use image node_id 4 for calling the DisCRnDataset obj's underlying member method code with example usage: obj.get_existing_audio_annotations() and returns: unknown