Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
This card is used to Ritual Summon "Skull Guardian". You must also offer monsters whose total Level Stars equal 7 or more as a Tribute from the field or your hand.
--ローの祈り
--Novox's Prayer
local s,id=GetID()
function s.initial_effect(c)
	Ritual.AddProcGreaterCode(c,7,nil,3627449)
end