Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
2 Level 4 Warrior monsters Once per turn: You can detach 2 materials from this card; this card's ATK becomes double its original ATK until the end of your opponent's turn.
--H－C エクスカリバー
--Heroic Champion - Excalibur
local s,id=GetID()
function s.initial_effect(c)
	--xyz summon
	Xyz.AddProcedure(c,aux.FilterBoolFunctionEx(Card.IsRace,RACE_WARRIOR),4,2)
	c:EnableReviveLimit()
	--attack up
	local e1=Effect.CreateEffect(c)
	e1:SetCategory(CATEGORY_ATKCHANGE)
	e1:SetDescription(aux.Stringid(id,0))
	e1:SetType(EFFECT_TYPE_IGNITION)
	e1:SetCountLimit(1)
	e1:SetRange(LOCATION_MZONE)
	e1:SetCost(Cost.DetachFromSelf(2))
	e1:SetOperation(s.operation)
	c:RegisterEffect(e1)
end
function s.operation(e,tp,eg,ep,ev,re,r,rp)
	local c=e:GetHandler()
	if c:IsRelateToEffect(e) and c:IsFaceup() then
		local e1=Effect.CreateEffect(c)
		e1:SetType(EFFECT_TYPE_SINGLE)
		e1:SetCode(EFFECT_SET_ATTACK_FINAL)
		e1:SetValue(c:GetBaseAttack()*2)
		e1:SetReset(RESETS_STANDARD_DISABLE_PHASE_END,2)
		c:RegisterEffect(e1)
	end
end