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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 _normalize(self, flags):
 """Take any format of flags and turn it into a hex string."""

        norm = None
        if isinstance(flags, MessageFlags):
            norm = flags.bytes
        elif isinstance(flags, bytearray):
            norm = binascii.hexlify(flags)
        elif isinstance(flags, int):
            norm = bytes([flags])
        elif isinstance(flags, bytes):
            norm = binascii.hexlify(flags)
        elif isinstance(flags, str):
            flags = flags[0:2]
            norm = binascii.hexlify(binascii.unhexlify(flags.lower()))
        elif flags is None:
            norm = None
        else:
            _LOGGER.warning('MessageFlags with unknown type %s: %r',
                            type(flags), flags)
        return norm