code: def test_cora_load_str() -> None:
      g, subjects = Cora().load(str_node_ids=True)
  
      # if everything is wrong, a top-level == gives better errors
      assert type(g.nodes()[0]) == str
      # but still good to check everything
      assert all(type(n) == str for n in g.nodes())
  
      assert set(subjects.index) == set(g.nodes())
  
imports: import pytest
  import tempfile
  import os
  import sys
  import numpy
  from stellargraph.datasets import *
  from urllib.error import URLError
  from stellargraph.datasets.dataset_loader import DatasetLoader
  from urllib.request import urlretrieve
  from unittest.mock import patch
label_desc: Use image node_id 13 for calling a global function with example usage: test_cora_load_str() without return types