Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
Each face-up Xyz Monster you control gains 300 ATK for each Xyz Material attached to it, until the End Phase.
--強化空間
--Reinforced Space
local s,id=GetID()
function s.initial_effect(c)
	--Activate
	local e1=Effect.CreateEffect(c)
	e1:SetCategory(CATEGORY_ATKCHANGE)
	e1:SetType(EFFECT_TYPE_ACTIVATE)
	e1:SetProperty(EFFECT_FLAG_DAMAGE_STEP)
	e1:SetCode(EVENT_FREE_CHAIN)
	e1:SetHintTiming(TIMING_DAMAGE_STEP)
	e1:SetCondition(aux.StatChangeDamageStepCondition)
	e1:SetTarget(s.target)
	e1:SetOperation(s.activate)
	c:RegisterEffect(e1)
end
function s.filter(c)
	return c:IsFaceup() and c:GetOverlayCount()~=0
end
function s.target(e,tp,eg,ep,ev,re,r,rp,chk)
	if chk==0 then return Duel.IsExistingMatchingCard(s.filter,tp,LOCATION_MZONE,0,1,nil) end
end
function s.activate(e,tp,eg,ep,ev,re,r,rp)
	local g=Duel.GetMatchingGroup(s.filter,tp,LOCATION_MZONE,0,nil)
	for tc in g:Iter() do
		local e1=Effect.CreateEffect(e:GetHandler())
		e1:SetType(EFFECT_TYPE_SINGLE)
		e1:SetCode(EFFECT_UPDATE_ATTACK)
		e1:SetReset(RESETS_STANDARD_PHASE_END)
		e1:SetValue(tc:GetOverlayCount()*300)
		tc:RegisterEffect(e1)
	end
end