How to revert to default third person camera?

So I have a local script called "CameraScript" which overwrites the default script:

--services

local UserInputService = game:GetService("UserInputService")
local RunService = game:GetService("RunService")
local Players = game:GetService("Players")

--constants

local LOCAL_PLAYER = Players.LocalPlayer
local CAMERA = workspace.CurrentCamera
local CHARACTER = LOCAL_PLAYER.Character or LOCAL_PLAYER.CharacterAdded:Wait()
local HUMANOID = CHARACTER:WaitForChild("Humanoid")
local HUMANOID_ROOT_PART = HUMANOID.RootPart
local CHARACTERS = workspace:WaitForChild("Characters")

--variables

local x = 0
local y = 0

local vx = 0
local vy = 0

--functions

--initiate

CAMERA.FieldOfView = 80
CAMERA.CameraType = Enum.CameraType.Custom
CAMERA.CameraSubject = CHARACTER

UserInputService.MouseBehavior = Enum.MouseBehavior.LockCenter

RunService:BindToRenderStep("Camera", Enum.RenderPriority.Last.Value, function(dt)
	CAMERA.Focus = CFrame.new(HUMANOID_ROOT_PART.Position)
	
	x = (x - vx * (1/260)) % (math.pi * 2)
	y = math.clamp(y - vy * (1/260), -1.4, 0.5)
	
	local center = HUMANOID_ROOT_PART.Position + Vector3.new(0, 4, 0)
	local cframe = CFrame.new(center) * CFrame.Angles(0, x, 0) * CFrame.Angles(y, 0, 0) * CFrame.new(0, 0, 20)
	local rotation = cframe - cframe.p
	
	local ray = Ray.new(center, (cframe.p - HUMANOID_ROOT_PART.Position))
	local _, position = workspace:FindPartOnRayWithIgnoreList(ray, {})
	
	CAMERA.CFrame = CFrame.new(position) * rotation

	if vx < 0 then
		vx = vx + 0.1
	elseif vx > 0 then
		vx = vx - 0.1
	end
	if vy < 0 then
		vy = vy + 0.1
	elseif vy > 0 then
		vy = vy - 0.1
	end
end)


UserInputService.InputChanged:connect(function(inputObject, processed)
	if not processed then
		if vx < 10 and vx > -10 then
			vx = vx + inputObject.Delta.X * 0.05
		end
		if vy < 10 and vy > -10 then
			vy = vy + inputObject.Delta.Y * 0.05
		end
	end
end)


LOCAL_PLAYER.CharacterAdded:Connect(function(character)
	CHARACTER = LOCAL_PLAYER.Character or LOCAL_PLAYER.CharacterAdded:Wait()
	HUMANOID = CHARACTER:WaitForChild("Humanoid")
	HUMANOID_ROOT_PART = HUMANOID.RootPart
end)

The script works fine, but I don't know how to make the script also include a way to revert the player's camera back and forth the default third person camera. Any ideas?