Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
Target 1 of your banished LIGHT Tuners and 1 of your banished Level 8 or lower DARK non-Tuners; return both to the GY, then Special Summon 1 LIGHT or DARK Synchro Monster from your Extra Deck whose Level equals the total Levels of those returned monsters.
--混沌変幻
--Chaos Phantasm
--scripted by Naim
local s,id=GetID()
function s.initial_effect(c)
	--Activate
	local e1=Effect.CreateEffect(c)
	e1:SetDescription(aux.Stringid(id,0))
	e1:SetCategory(CATEGORY_TOGRAVE+CATEGORY_SPECIAL_SUMMON)
	e1:SetType(EFFECT_TYPE_ACTIVATE)
	e1:SetProperty(EFFECT_FLAG_CARD_TARGET)
	e1:SetCode(EVENT_FREE_CHAIN)
	e1:SetHintTiming(0,TIMING_END_PHASE)
	e1:SetTarget(s.target)
	e1:SetOperation(s.activate)
	c:RegisterEffect(e1)
end
function s.tgfilter(c,e)
	if not (c:IsFaceup() and c:HasLevel() and c:IsCanBeEffectTarget(e)) then return false end
	if c:IsAttribute(ATTRIBUTE_LIGHT) then
		return c:IsType(TYPE_TUNER)
	elseif c:IsAttribute(ATTRIBUTE_DARK) then
		return not c:IsType(TYPE_TUNER) and c:IsLevelBelow(8)
	end
	return false
end
function s.rescon(sg,e,tp,mg)
	return #sg==2 and sg:IsExists(Card.IsAttribute,1,nil,ATTRIBUTE_LIGHT) and sg:IsExists(Card.IsAttribute,1,nil,ATTRIBUTE_DARK)
		and Duel.IsExistingMatchingCard(s.spfilter,tp,LOCATION_EXTRA,0,1,nil,e,tp,sg:GetSum(Card.GetLevel))
end
function s.spfilter(c,e,tp,lvl)
	return c:IsLevel(lvl) and c:IsType(TYPE_SYNCHRO) and c:IsAttribute(ATTRIBUTE_LIGHT|ATTRIBUTE_DARK)
		and Duel.GetLocationCountFromEx(tp,tp,nil,c)>0 and c:IsCanBeSpecialSummoned(e,0,tp,false,false)
end
function s.target(e,tp,eg,ep,ev,re,r,rp,chk,chkc)
	local g=Duel.GetMatchingGroup(s.tgfilter,tp,LOCATION_REMOVED,0,nil,e)
	if chkc then return chkc:IsLocation(LOCATION_REMOVED) and s.tgfilter(chkc,e) end
	if chk==0 then return aux.SelectUnselectGroup(g,e,tp,2,2,s.rescon,0) end
	local tg=aux.SelectUnselectGroup(g,e,tp,2,2,s.rescon,1,tp,HINTMSG_TOGRAVE)
	Duel.SetTargetCard(tg)
	Duel.SetOperationInfo(0,CATEGORY_TOGRAVE,tg,#tg,0,0)
	Duel.SetOperationInfo(0,CATEGORY_SPECIAL_SUMMON,nil,1,tp,LOCATION_EXTRA)
end
function s.activate(e,tp,eg,ep,ev,re,r,rp)
	local tg=Duel.GetTargetCards(e)
	if #tg==2 and Duel.SendtoGrave(tg,REASON_EFFECT|REASON_RETURN)==2 then
		local og=Duel.GetOperatedGroup()
		if og:FilterCount(Card.IsLocation,nil,LOCATION_GRAVE)~=2 then return end
		local lvl=tg:GetSum(Card.GetLevel)
		Duel.Hint(HINT_SELECTMSG,tp,HINTMSG_SPSUMMON)
		local g=Duel.SelectMatchingCard(tp,s.spfilter,tp,LOCATION_EXTRA,0,1,1,nil,e,tp,lvl)
		if #g>0 then
			Duel.BreakEffect()
			Duel.SpecialSummon(g,0,tp,tp,false,false,POS_FACEUP)
		end
	end
end