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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _load_fast(filename):
 """Sub for fast loader."""

        it = json.load(open("{}_items.json".format(filename)))
        words, unk_index, name = it["items"], it["unk_index"], it["name"]
        vectors = np.load(open("{}_vectors.npy".format(filename), 'rb'))
        return words, unk_index, name, vectors