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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_s16(self, msb, lsb):
 """ Convert 2 bytes into a signed int. """

        buf = struct.pack('>bB', self._get_s8(msb), self._get_u8(lsb))
        return int(struct.unpack('>h', buf)[0])