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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 _guess_type(mrz_lines):
 """Guesses the type of the MRZ from given lines. Returns 'TD1', 'TD2', 'TD3', 'MRVA', 'MRVB' or None. The algorithm is basically just counting lines, looking at their length and checking whether the first character is a 'V' True True True 'TD2' 'TD3' 'TD1' 'MRVA' 'MRVB' """

        try:
            if len(mrz_lines) == 3:
                return 'TD1'
            elif len(mrz_lines) == 2 and len(mrz_lines[0]) < 40 and len(mrz_lines[1]) < 40:
                return 'MRVB' if mrz_lines[0][0].upper() == 'V' else 'TD2'
            elif len(mrz_lines) == 2:
                return 'MRVA' if mrz_lines[0][0].upper() == 'V' else 'TD3'
            else:
                return None
        except Exception: #pylint: disable=broad-except
            return None