@classmethod
def from_combined_bin(cls, combined_bin):
    """Given the data and tag master keys in binary, validate and
        unpack them.

        :param bytes combined_bin: The binary data and tag master key
        :return: Two instances of :class:`AmiiboMasterKey`.
        :raises ValueError: If the binary data is invalid
        """
    count = len(combined_bin)
    if count != 160:
        raise ValueError('Data is {} bytes (should be 160).'.format(count))
    return cls.from_separate_bin(combined_bin[:80], combined_bin[80:])
