Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
If this card is Normal Summoned: Banish 1 or more DARK monsters from your GY, and if you do, this card gains 400 ATK for each, until the end of this turn.
--闇王プロメティス
--Prometheus, King of the Shadows
local s,id=GetID()
function s.initial_effect(c)
	--Banish 1 or more DARK monsters from your GY, and if you do, this card gains 400 ATK for each, until the end of this turn
	local e1=Effect.CreateEffect(c)
	e1:SetDescription(aux.Stringid(id,0))
	e1:SetCategory(CATEGORY_REMOVE+CATEGORY_ATKCHANGE)
	e1:SetType(EFFECT_TYPE_SINGLE+EFFECT_TYPE_TRIGGER_F)
	e1:SetCode(EVENT_SUMMON_SUCCESS)
	e1:SetTarget(s.rmtg)
	e1:SetOperation(s.rmop)
	c:RegisterEffect(e1)
end
function s.rmtg(e,tp,eg,ep,ev,re,r,rp,chk)
	if chk==0 then return true end
	Duel.SetOperationInfo(0,CATEGORY_REMOVE,nil,1,tp,LOCATION_GRAVE)
end
function s.rmfilter(c)
	return c:IsAttribute(ATTRIBUTE_DARK) and c:IsAbleToRemove() and aux.SpElimFilter(c,true)
end
function s.rmop(e,tp,eg,ep,ev,re,r,rp)
	local max_ct=Duel.GetMatchingGroupCount(s.rmfilter,tp,LOCATION_MZONE|LOCATION_GRAVE,0,nil)
	if max_ct==0 then return end
	local c=e:GetHandler()
	Duel.Hint(HINT_SELECTMSG,tp,HINTMSG_REMOVE)
	local g=Duel.SelectMatchingCard(tp,s.rmfilter,tp,LOCATION_MZONE|LOCATION_GRAVE,0,1,max_ct,nil)
	local ct=Duel.Remove(g,POS_FACEUP,REASON_EFFECT)
	if ct>0 and c:IsFaceup() and c:IsRelateToEffect(e) then
		--This card gains 400 ATK for each, until the end of this turn
		local e1=Effect.CreateEffect(c)
		e1:SetType(EFFECT_TYPE_SINGLE)
		e1:SetCode(EFFECT_UPDATE_ATTACK)
		e1:SetValue(ct*400)
		e1:SetReset(RESETS_STANDARD_DISABLE_PHASE_END)
		c:RegisterEffect(e1)
	end
end