def test_issue3882(en_vocab):
    """Test that displaCy doesn't serialize the doc.user_data when making a
    copy of the Doc.
    """
    doc = Doc(en_vocab, words=["Hello", "world"], deps=["dep", "dep"])
    doc.user_data["test"] = set()
    displacy.parse_deps(doc)
Test that displaCy doesn't serialize the doc.user_data when making a
    copy of the Doc.
    
spacy/tests/test_displacy.py