code: def get_anno(self):
      if self.anno_path is None:
          return
      if self.dataset_dir:
          return os.path.join(self.dataset_dir, self.anno_path)
      else:
          return self.anno_path
  
imports: import os
  import copy
  import numpy
  from paddle.io import Dataset
  from ppdet.core.workspace import register, serializable
  from ppdet.utils.download import get_dataset_path
  from ppdet.data import source
  from ppdet.utils.logger import setup_logger
label_desc: Use image node_id 3 for calling the ImageFolder obj's underlying member method code with example usage: obj.get_anno() and returns: os, self