[Closed] Checking for photometric Lights

Any ideas on how I can check a scene for photometric lights? The only thing I could think of was to see if the lights have the distribution property. This works on photometric lights but throws an error on standard lights. Any ideas?

for i = 1 to lights.count do
	(
	  if classof  lights[i] != Targetobject then
	  (	 
	   if  lights[i].distribution != undefined then
	   (
		messageBox "Photometric lights are not supported"
	   )
	   else
	   (
		print "standard Light"
	   )
	  )
	)