Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
Once per turn: You can send 1 Trap from your hand to the GY; Special Summon 1 Level 4 or lower "Ninja" monster from your Deck in face-up Defense Position or face-down Defense Position.
--成金忍者
--Upstart Golden Ninja
local s,id=GetID()
function s.initial_effect(c)
	--to hand
	local e1=Effect.CreateEffect(c)
	e1:SetDescription(aux.Stringid(id,0))
	e1:SetCategory(CATEGORY_SPECIAL_SUMMON)
	e1:SetType(EFFECT_TYPE_IGNITION)
	e1:SetRange(LOCATION_MZONE)
	e1:SetCountLimit(1)
	e1:SetCost(s.cost)
	e1:SetTarget(s.target)
	e1:SetOperation(s.operation)
	c:RegisterEffect(e1)
end
s.listed_series={SET_NINJA}
function s.costfilter(c)
	return c:IsTrap() and c:IsAbleToGraveAsCost()
end
function s.cost(e,tp,eg,ep,ev,re,r,rp,chk)
	if chk==0 then return Duel.IsExistingMatchingCard(s.costfilter,tp,LOCATION_HAND,0,1,nil) end
	Duel.Hint(HINT_SELECTMSG,tp,HINTMSG_TOGRAVE)
	local cg=Duel.SelectMatchingCard(tp,s.costfilter,tp,LOCATION_HAND,0,1,1,nil)
	Duel.SendtoGrave(cg,REASON_COST)
end
function s.filter(c,e,tp)
	return c:IsLevelBelow(4) and c:IsSetCard(SET_NINJA) and
		c:IsCanBeSpecialSummoned(e,0,tp,false,false,POS_DEFENSE)
end
function s.target(e,tp,eg,ep,ev,re,r,rp,chk)
	if chk==0 then return Duel.GetLocationCount(tp,LOCATION_MZONE)>0
		and Duel.IsExistingMatchingCard(s.filter,tp,LOCATION_DECK,0,1,nil,e,tp) end
	Duel.SetOperationInfo(0,CATEGORY_SPECIAL_SUMMON,nil,1,tp,LOCATION_DECK)
end
function s.operation(e,tp,eg,ep,ev,re,r,rp,chk)
	if Duel.GetLocationCount(tp,LOCATION_MZONE)<=0 then return end
	Duel.Hint(HINT_SELECTMSG,tp,HINTMSG_SPSUMMON)
	local g=Duel.SelectMatchingCard(tp,s.filter,tp,LOCATION_DECK,0,1,1,nil,e,tp)
	local tc=g:GetFirst()
	if not tc then return end
	if Duel.SpecialSummon(tc,0,tp,tp,false,false,POS_DEFENSE)~=0 and tc:IsFacedown() then
		Duel.ConfirmCards(1-tp,tc)
	end
end