Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
If you control a "Blackwing" monster: Destroy all face-down Spells and Traps your opponent controls. If you control exactly 3 "Blackwing" monsters, you can activate this card from your hand.
--デルタ・クロウ－アンチ・リバース
--Delta Crow - Anti Reverse
local s,id=GetID()
function s.initial_effect(c)
	--Destroy all face-down Spell/Trap cards your opponent controls
	local e1=Effect.CreateEffect(c)
	e1:SetCategory(CATEGORY_DESTROY)
	e1:SetType(EFFECT_TYPE_ACTIVATE)
	e1:SetCode(EVENT_FREE_CHAIN)
	e1:SetHintTiming(0,TIMING_END_PHASE)
	e1:SetCondition(s.condition)
	e1:SetTarget(s.target)
	e1:SetOperation(s.activate)
	c:RegisterEffect(e1)
	--Can be activated from the hand
	local e2=Effect.CreateEffect(c)
	e2:SetDescription(aux.Stringid(id,0))
	e2:SetType(EFFECT_TYPE_SINGLE)
	e2:SetCode(EFFECT_TRAP_ACT_IN_HAND)
	e2:SetCondition(s.handcon)
	c:RegisterEffect(e2)
end
s.listed_series={SET_BLACKWING}
function s.handcon(e)
	return Duel.GetMatchingGroupCount(s.cfilter,e:GetHandler():GetControler(),LOCATION_MZONE,0,nil)==3
end
function s.cfilter(c)
	return c:IsFaceup() and c:IsSetCard(SET_BLACKWING)
end
function s.condition(e,tp,eg,ep,ev,re,r,rp)
	return Duel.IsExistingMatchingCard(s.cfilter,tp,LOCATION_MZONE,0,1,nil)
end
function s.target(e,tp,eg,ep,ev,re,r,rp,chk)
	if chk==0 then return Duel.IsExistingMatchingCard(Card.IsFacedown,tp,0,LOCATION_SZONE,1,nil) end
	local g=Duel.GetMatchingGroup(Card.IsFacedown,tp,0,LOCATION_SZONE,nil)
	Duel.SetOperationInfo(0,CATEGORY_DESTROY,g,#g,0,0)
end
function s.activate(e,tp,eg,ep,ev,re,r,rp)
	local g=Duel.GetMatchingGroup(Card.IsFacedown,tp,0,LOCATION_SZONE,nil)
	Duel.Destroy(g,REASON_EFFECT)
end