Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
Discard 1 Monster Card from your hand to the Graveyard. Select 1 monster on your side of the field with a lower Level than the discarded monster. The selected monster can attack twice this turn.
--ダブルアタック
--Double Attack
local s,id=GetID()
function s.initial_effect(c)
	--Activate
	local e1=Effect.CreateEffect(c)
	e1:SetType(EFFECT_TYPE_ACTIVATE)
	e1:SetCode(EVENT_FREE_CHAIN)
	e1:SetProperty(EFFECT_FLAG_CARD_TARGET)
	e1:SetLabel(0)
	e1:SetCondition(s.condition)
	e1:SetCost(s.cost)
	e1:SetTarget(s.target)
	e1:SetOperation(s.activate)
	c:RegisterEffect(e1)
end
function s.condition(e,tp,eg,ep,ev,re,r,rp)
	return Duel.IsAbleToEnterBP()
end
function s.cost(e,tp,eg,ep,ev,re,r,rp,chk)
	e:SetLabel(1)
	return true
end
function s.filter1(c,tp)
	local lv=c:GetOriginalLevel()
	return lv>1 and c:IsMonster() and c:IsDiscardable() and c:IsAbleToGraveAsCost()
		and Duel.IsExistingTarget(s.filter2,tp,LOCATION_MZONE,0,1,nil,lv)
end
function s.filter2(c,lv)
	return c:IsFaceup() and c:IsLevelBelow(lv-1) and not c:IsHasEffect(EFFECT_EXTRA_ATTACK)
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.filter2(chkc,e:GetLabel()) end
	if chk==0 then
		if e:GetLabel()~=1 then return false end
		e:SetLabel(0)
		return Duel.IsExistingMatchingCard(s.filter1,tp,LOCATION_HAND,0,1,nil,tp)
	end
	Duel.Hint(HINT_SELECTMSG,tp,HINTMSG_DISCARD)
	local cg=Duel.SelectMatchingCard(tp,s.filter1,tp,LOCATION_HAND,0,1,1,nil,tp)
	Duel.SendtoGrave(cg,REASON_DISCARD|REASON_COST)
	local lv=cg:GetFirst():GetLevel()
	e:SetLabel(lv)
	Duel.Hint(HINT_SELECTMSG,tp,HINTMSG_FACEUP)
	Duel.SelectTarget(tp,s.filter2,tp,LOCATION_MZONE,0,1,1,nil,lv)
end
function s.activate(e,tp,eg,ep,ev,re,r,rp)
	local tc=Duel.GetFirstTarget()
	if tc:IsRelateToEffect(e) then
		local e1=Effect.CreateEffect(e:GetHandler())
		e1:SetType(EFFECT_TYPE_SINGLE)
		e1:SetCode(EFFECT_EXTRA_ATTACK)
		e1:SetValue(1)
		e1:SetReset(RESETS_STANDARD_PHASE_END)
		tc:RegisterEffect(e1)
	end
end