code: def get_existing_pc_annotations(self):
      return list(
          set(os.listdir(self.pc_root)).intersection(
              set(ann["sample_id"] for ann in self.annotation)
          )
      )
  
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 3 for calling the ObjaverseCaptionDataset obj's underlying member method code with example usage: obj.get_existing_pc_annotations() and returns: list