code: def test_doc_extensions(doc):
      assert all(hasattr(doc._, attr) for attr in ["preview", "meta"])
      assert isinstance(doc._.preview, str)
      assert isinstance(doc._.meta, dict)
  
imports: import collections
  import itertools
  import re
  import pytest
  from spacy.tokens import Span
  import textacy
  import textacy.datasets
  import textacy.extract
  import textacy.preprocessing
label_desc: Use image node_id 10 for calling a global function with example usage: test_doc_extensions(doc) without return types