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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_from_file(cls, filename_prefix):
 """Extracts list of subwords from file."""

    filename = cls._filename(filename_prefix)
    lines, _ = cls._read_lines_from_file(filename)
    # Strip wrapping single quotes
    vocab_list = [line[1:-1] for line in lines]
    return cls(vocab_list=vocab_list)