code: def test_history_partial_index(self, history, ref):
      extra = history[:, "extra"]
      assert len(extra) == 1
      # we retrieve 'extra' from a slice, therefore we expect a list as result
      assert extra == [ref[2]["extra"]]
  
imports: import pickle
  import time
  import multiprocessing
  from functools import partial
  import numpy
  import pytest
  import torch
  from torch.distributed import TCPStore
  from sklearn.datasets import make_classification
label_desc: Use image node_id 9 for calling the TestHistory obj's underlying member method code with example usage: obj.test_history_partial_index(history, ref) without return types