code: def __len__(self):
      return len(self.data)
  
imports: import os
  import sys
  import json
  import numpy
  import glob
  import copy
  import time
  import argparse
  from collections import OrderedDict, namedtuple
  from scipy.sparse import csr_matrix
  from ogb.graphproppred import GraphPropPredDataset
  from ogb.utils.features import get_atom_feature_dims, get_bond_feature_dims
  import pgl
  import paddle
  from pgl.utils.data.dataset import Dataset, StreamDataset, HadoopDataset
  from pgl.utils.data import Dataloader
  from pgl.utils.logger import log
  from utils.config import prepare_config, make_dir
label_desc: Use image node_id 3 for calling the ShardedDataset obj's underlying member method code with example usage: obj.__len__() and returns: len