code: def __len__(self):
      return len(self.data_idx_order_list)
  
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 5 for calling the PGDataSet obj's underlying member method code with example usage: obj.__len__() and returns: len