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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 x10(cls, housecode, unitcode):
 """Create an X10 device address."""

        if housecode.lower() in ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h',
                                 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p']:
            byte_housecode = insteonplm.utils.housecode_to_byte(housecode)
        else:
            if isinstance(housecode, str):
                _LOGGER.error('X10 house code error: %s', housecode)
            else:
                _LOGGER.error('X10 house code is not a string')
            raise ValueError

        # 20, 21 and 22 for All Units Off, All Lights On and All Lights Off
        # 'fake' units
        if unitcode in range(1, 17) or unitcode in range(20, 23):
            byte_unitcode = insteonplm.utils.unitcode_to_byte(unitcode)
        else:
            if isinstance(unitcode, int):
                _LOGGER.error('X10 unit code error: %d', unitcode)
            else:
                _LOGGER.error('X10 unit code is not an integer 1 - 16')
            raise ValueError

        addr = Address(bytearray([0x00, byte_housecode, byte_unitcode]))
        addr.is_x10 = True
        return addr