=LOWER(CONCATENATE(DEC2HEX(RANDBETWEEN(0,POWER(16,8)),8),"",DEC2HEX(RANDBETWEEN(0,POWER(16,4)),4),"","4",DEC2HEX(RANDBETWEEN(0,POWER(16,3)),3),"",DEC2HEX(RANDBETWEEN(8,11)),DEC2HEX(RANDBETWEEN(0,POWER(16,3)),3),"",DEC2HEX(RANDBETWEEN(0,POWER(16,8)),8),DEC2HEX(RANDBETWEEN(0,POWER(16,4)),4)))