code: def __getitem__(self, idx):
      lmdb_idx, file_idx = self.data_idx_order_list[idx]
      lmdb_idx = int(lmdb_idx)
      file_idx = int(file_idx)
      sample_info = self.get_lmdb_sample_info(
          self.lmdb_sets[lmdb_idx]["txn"], file_idx
      )
      if sample_info is None:
          return self.__getitem__(np.random.randint(self.__len__()))
      img_HR, img_lr, label_str = sample_info
      data = {
          "image_hr": img_HR,
          "image_lr": img_lr,
          "label": label_str,
      }
      outs = transform(data, self.ops)
      if outs is None:
          return self.__getitem__(np.random.randint(self.__len__()))
      return outs
  
imports: import numpy
  import os
  from paddle.io import Dataset
  import lmdb
  import cv2
  import string
  import six
  import pickle
  from PIL import Image
  from .imaug import transform, create_operators
label_desc: Use image node_id 4 for calling the LMDBDataSetSR obj's underlying member method code with example usage: obj.__getitem__(idx) and returns: outs, self, self