Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
Activate only when a Reptile-Type monster you control is destroyed. Special Summon 1 Level 4 or lower Reptile-Type monster from your Deck.
--スネーク・ホイッスル
--Snake Whistle
local s,id=GetID()
function s.initial_effect(c)
	--Activate
	local e1=Effect.CreateEffect(c)
	e1:SetCategory(CATEGORY_SPECIAL_SUMMON)
	e1:SetType(EFFECT_TYPE_ACTIVATE)
	e1:SetCode(EVENT_DESTROYED)
	e1:SetCondition(s.condition)
	e1:SetTarget(s.target)
	e1:SetOperation(s.activate)
	c:RegisterEffect(e1)
end
function s.cfilter(c,tp)
	return c:IsRace(RACE_REPTILE) and c:IsPreviousPosition(POS_FACEUP) and c:IsPreviousControler(tp)
		and c:IsPreviousLocation(LOCATION_MZONE)
end
function s.condition(e,tp,eg,ep,ev,re,r,rp)
	return eg:IsExists(s.cfilter,1,nil,tp)
end
function s.filter(c,e,tp)
	return c:IsLevelBelow(4) and c:IsRace(RACE_REPTILE) and c:IsCanBeSpecialSummoned(e,0,tp,false,false)
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.activate(e,tp,eg,ep,ev,re,r,rp)
	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 tc then
		Duel.SpecialSummon(tc,0,tp,tp,false,false,POS_FACEUP)
	end
end