code: def test_PairDataset():
      config_file = "../../../config.yaml"
      ip_list_file = "../../../ip_list.txt"
      config = prepare_config(config_file)
  
      ds = TrainPairDataset(config, ip_list_file)
  
      loader = Dataloader(
          ds,
          batch_size=4,
          num_workers=1,
          stream_shuffle_size=100,
          collate_fn=CollateFn(),
      )
      pairs = []
      start = time.time()
      for batch_data in loader:
          pairs.extend(batch_data)
          print(batch_data)
          time.sleep(10)
      print("total time: %s" % (time.time() - start))
  
imports: import os
  import sys
  import time
  import warnings
  import numpy
  from collections import defaultdict
  from pgl.graph_kernel import skip_gram_gen_pair
  from pgl.utils.logger import log
  from pgl.distributed import DistGraphClient, DistGraphServer
  from pgl.utils.data import Dataloader, StreamDataset
  from utils.config import prepare_config
  from datasets.node import NodeGenerator
  from datasets.walk import WalkGenerator
  from datasets.pair import PairGenerator
label_desc: Use image node_id 1 for calling a global function with example usage: test_PairDataset() without return types