code: def get_existing_images_annotations(self):
      return os.listdir(self.vis_root)
  
imports: import os
  from collections import OrderedDict
  import torch
  import copy
  import pathlib
  import random
  import json
  import pandas
  import torchaudio
  import torch
  from tqdm import tqdm
  from lavis.datasets.datasets.base_dataset import BaseDataset
label_desc: Use image node_id 6 for calling the ESC50 obj's underlying member method code with example usage: obj.get_existing_images_annotations() and returns: os