code: def __getitem__(self, idx):
      file_idx = self.data_idx_order_list[idx]
      data_line = self.data_lines[file_idx]
      img_id = 0
      try:
          data_line = data_line.decode("utf-8")
          substr = data_line.strip("\n").split(self.delimiter)
          file_name = substr[0]
          label = substr[1]
          img_path = os.path.join(self.data_dir, file_name)
          if self.mode.lower() == "eval":
              try:
                  img_id = int(data_line.split(".")[0][7:])
              except:
                  img_id = 0
          data = {
              "img_path": img_path,
              "label": label,
              "img_id": img_id,
          }
          if not os.path.exists(img_path):
              raise Exception("{} does not exist!".format(img_path))
          with open(data["img_path"], "rb") as f:
              img = f.read()
              data["image"] = img
          outs = transform(data, self.ops)
      except Exception as e:
          self.logger.error(
              "When parsing line {}, error happened with msg: {}".format(
                  self.data_idx_order_list[idx], e
              )
          )
          outs = None
      if outs is None:
          return self.__getitem__(np.random.randint(self.__len__()))
      return outs
  
file_path: PaddleOCR/ppocr/data/pgnet_dataset.py
imports: import numpy
  import os
  from paddle.io import Dataset
  from .imaug import transform, create_operators
  import random
label_desc: Use image node_id 4 for calling the PGDataSet obj's underlying member method code with example usage: obj.__getitem__(idx) and returns: outs, self