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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 get_corpus(filename: str) -> frozenset: """ Read corpus from file and return a frozenset :param string filename: file corpus """

    lines = []
    with open(os.path.join(corpus_path(), filename), "r", encoding="utf-8-sig") as fh:
        lines = fh.read().splitlines()

    return frozenset(lines)