Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
When the control of this face-up card on the field shifts to your opponent, inflict 2000 points of damage to your opponent's Life Points. This effect can only be used once as long as this card remains face-up on the field.
--アメーバ
--Ameba
local s,id=GetID()
function s.initial_effect(c)
	--damage
	local e1=Effect.CreateEffect(c)
	e1:SetDescription(aux.Stringid(id,0))
	e1:SetCategory(CATEGORY_DAMAGE)
	e1:SetType(EFFECT_TYPE_SINGLE+EFFECT_TYPE_TRIGGER_F)
	e1:SetCode(EVENT_CONTROL_CHANGED)
	e1:SetProperty(EFFECT_FLAG_NO_TURN_RESET)
	e1:SetCountLimit(1)
	e1:SetTarget(s.target)
	e1:SetOperation(s.operation)
	c:RegisterEffect(e1)
end
function s.target(e,tp,eg,ep,ev,re,r,rp,chk)
	if chk==0 then return not e:GetHandler():IsStatus(STATUS_CHAINING) end
	Duel.SetOperationInfo(0,CATEGORY_DAMAGE,nil,0,tp,2000)
end
function s.operation(e,tp,eg,ep,ev,re,r,rp)
	Duel.Damage(tp,2000,REASON_EFFECT)
end