How to use the sense2vec.util.make_key function in sense2vec

def test_make_split_key(word, sense, expected):
    assert make_key(word, sense) == expected
    assert split_key(expected) == (word, sense)

with input_path.open("rb") as f:
        doc_bin_bytes = f.read()
    doc_bin = DocBin().from_bytes(doc_bin_bytes)
    msg.good(f"Loaded {len(doc_bin)} parsed docs")
    docs = doc_bin.get_docs(nlp.vocab)
    output_file = output_path / f"{input_path.stem}.s2v"
    lines_count = 0
    words_count = 0
    with output_file.open("w", encoding="utf8") as f:
        for doc in tqdm.tqdm(docs, desc="Docs", unit=""):
            doc = merge_phrases(doc)
            words = []
            for token in doc:
                if not token.is_space:
                    word, sense = make_spacy_key(token, prefer_ents=True)
                    words.append(make_key(word, sense))
            f.write(" ".join(words) + "\n")
            lines_count += 1
            words_count += len(words)
    msg.good(
        f"Successfully preprocessed {lines_count} docs ({words_count} words)",
        output_file.resolve(),
    )