Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
If this card is in your Graveyard: You can target 1 Level 5 or higher monster you control; reduce its Level by 1, and if you do, Special Summon this card. This face-up card on the field cannot be Tributed, except for a Tribute Summon.
--レベル・スティーラー
--Level Eater
local s,id=GetID()
function s.initial_effect(c)
	--spsummon
	local e1=Effect.CreateEffect(c)
	e1:SetDescription(aux.Stringid(id,0))
	e1:SetCategory(CATEGORY_SPECIAL_SUMMON)
	e1:SetProperty(EFFECT_FLAG_CARD_TARGET)
	e1:SetType(EFFECT_TYPE_IGNITION)
	e1:SetRange(LOCATION_GRAVE)
	e1:SetTarget(s.target)
	e1:SetOperation(s.operation)
	c:RegisterEffect(e1)
	--unreleaseable nonsum
	local e2=Effect.CreateEffect(c)
	e2:SetType(EFFECT_TYPE_SINGLE)
	e2:SetProperty(EFFECT_FLAG_SINGLE_RANGE)
	e2:SetRange(LOCATION_MZONE)
	e2:SetCode(EFFECT_UNRELEASABLE_NONSUM)
	e2:SetValue(1)
	c:RegisterEffect(e2)
end
function s.filter(c)
	return c:IsFaceup() and c:GetLevel()>=5
end
function s.target(e,tp,eg,ep,ev,re,r,rp,chk,chkc)
	if chkc then return chkc:IsLocation(LOCATION_MZONE) and chkc:IsControler(tp) and s.filter(chkc) end
	local c=e:GetHandler()
	if chk==0 then return Duel.IsExistingTarget(s.filter,tp,LOCATION_MZONE,0,1,nil)
		and Duel.GetLocationCount(tp,LOCATION_MZONE)>0 and c:IsCanBeSpecialSummoned(e,0,tp,false,false) end
	Duel.Hint(HINT_SELECTMSG,tp,aux.Stringid(id,1))
	Duel.SelectTarget(tp,s.filter,tp,LOCATION_MZONE,0,1,1,nil)
	Duel.SetOperationInfo(0,CATEGORY_SPECIAL_SUMMON,c,1,0,0)
end
function s.operation(e,tp,eg,ep,ev,re,r,rp)
	local tc=Duel.GetFirstTarget()
	if tc:IsFacedown() or not tc:IsRelateToEffect(e) or tc:IsImmuneToEffect(e) or tc:GetLevel()<2 then return end
	local c=e:GetHandler()
	local e1=Effect.CreateEffect(c)
	e1:SetType(EFFECT_TYPE_SINGLE)
	e1:SetCode(EFFECT_UPDATE_LEVEL)
	e1:SetReset(RESET_EVENT|RESETS_STANDARD)
	e1:SetValue(-1)
	tc:RegisterEffect(e1)
	if c:IsRelateToEffect(e) then
		Duel.SpecialSummon(c,0,tp,tp,false,false,POS_FACEUP)
	end
end