Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
When an opponent's monster declares an attack: Your opponent chooses 1 random card from your hand, then if it is a monster that can be Special Summoned, Special Summon it. Otherwise, send it to the GY.
--ヒーロー見参
--A Hero Emerges
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_ATTACK_ANNOUNCE)
	e1:SetCondition(s.condition)
	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.IsTurnPlayer(1-tp)
end
function s.spfilter(c,e,tp)
	return 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.spfilter,tp,LOCATION_HAND,0,1,nil,e,tp) end
end
function s.activate(e,tp,eg,ep,ev,re,r,rp)
	if Duel.GetLocationCount(tp,LOCATION_MZONE)<=0 or not Duel.IsPlayerCanSpecialSummon(tp) then return end
	local g=Duel.GetFieldGroup(tp,LOCATION_HAND,0)
	local sg=g:RandomSelect(1-tp,1)
	local tc=sg:GetFirst()
	if tc then
		Duel.ConfirmCards(1-tp,tc)
		if tc:IsCanBeSpecialSummoned(e,0,tp,false,false) then
			Duel.SpecialSummon(tc,0,tp,tp,false,false,POS_FACEUP)
		else
			Duel.SendtoGrave(tc,REASON_EFFECT)
		end
	end
end