code: def get_existing_pc_annotations(self):
      return list(
          set([f.replace(".npy", "") for f in os.listdir(self.pc_root)])
      )
  
imports: import os, sys
  from collections import OrderedDict
  import random
  from lavis.datasets.datasets.base_dataset import BaseDataset
  from lavis.common.utils import is_serializable
  from PIL import Image
  import numpy
  from tqdm import tqdm
  import json
  import torch
  import copy
label_desc: Use image node_id 2 for calling the ShapenetCaptionDataset obj's underlying member method code with example usage: obj.get_existing_pc_annotations() and returns: list