Classic - power word shield macro

Hello, I have macros set up on my healing spells that basically run through the following: mouseover, if that doesn’t exist then target, and if that doesn’t exist then self. The problem I have is power word shield. I know you can’t put it on a non party member, but I can’t even get a macro to work that is first mouseover, if no mouseover then self if I am targeting an enemy. Does anyone have some useful pws macros for pvp and raiding?