I just found this error in my script editor so here I'm looking for answers.

Well I don't know how to fix it but know a work around which solves most of these sort of issues. Which is deleting preferences and restarting Maya.

And for those of you who want to know when the error pops up...
Can't say exactly but I found the Light Shape swatch goes missing from your Spotlight Attribute Editor.

So far I guess it's just a swatch for previewing purpose and shouldn't be a problem. Otherwise we can always reset Maya Preference