isValidMac mac = ((map toUpper mac) =~ "^([0-9A-F]{2}[:-]){5}([0-9A-F]{2})$" :: Bool)
isValidMac mac = ((map toUpper mac) =~ "^([0-9A-F]{2}[:-]){5}([0-9A-F]{2})$" :: Bool)
isValidMac mac = ((map toUpper mac) =~ "^([0-9A-F]{2}[:-]){5}([0-9A-F]{2})$" :: Bool)