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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 read_option_value_from_nibble(nibble, pos, values):
 """ Calculates the value used in the extended option fields. :param nibble: the 4-bit option header value. :return: the value calculated from the nibble and the extended option value. """

        if nibble <= 12:
            return nibble, pos
        elif nibble == 13:
            tmp = struct.unpack("!B", values[pos].to_bytes(1, "big"))[0] + 13
            pos += 1
            return tmp, pos
        elif nibble == 14:
            s = struct.Struct("!H")
            tmp = s.unpack_from(values[pos:].to_bytes(2, "big"))[0] + 269
            pos += 2
            return tmp, pos
        else:
            raise AttributeError("Unsupported option nibble " + str(nibble))