Having a key switch Shift Lock for the camera?

I tried modifying the RootCamera script, but this doesn't work. What should I do? (lines modified/added: 7, 200-210)

local PlayersService = game:GetService('Players')
local UserInputService = game:GetService('UserInputService')
local StarterGui = game:GetService('StarterGui')
local GuiService = game:GetService('GuiService')
local ContextActionService = game:GetService('ContextActionService')
local VRService = game:GetService("VRService")
local UserInputService = game:GetService("UserInputService")

local LocalPlayer = PlayersService.LocalPlayer
local PlayerGui = nil
if LocalPlayer then
    PlayerGui = PlayersService.LocalPlayer:WaitForChild("PlayerGui")
end

local PortraitMode = false

local CameraScript = script.Parent
local ShiftLockController = require(CameraScript:WaitForChild('ShiftLockController'))

local Settings = UserSettings()
local GameSettings = Settings.GameSettings

local function clamp(low, high, num)
    return (num > high and high or num < low and low or num)
end

local math_atan2 = math.atan2
local function findAngleBetweenXZVectors(vec2, vec1)
    return math_atan2(vec1.X*vec2.Z-vec1.Z*vec2.X, vec1.X*vec2.X + vec1.Z*vec2.Z)
end

local function IsFinite(num)
    return num == num and num ~= 1/0 and num ~= -1/0
end

local THUMBSTICK_DEADZONE = 0.2

local LANDSCAPE_DEFAULT_ZOOM = 12.5
local PORTRAIT_DEFAULT_ZOOM = 25

local humanoidCache = {}
local function findPlayerHumanoid(player)
    local character = player and player.Character
    if character then
        local resultHumanoid = humanoidCache[player]
        if resultHumanoid and resultHumanoid.Parent == character then
            return resultHumanoid
        else
            humanoidCache[player] = nil -- Bust Old Cache
            local humanoid = character:FindFirstChildOfClass("Humanoid")
            if humanoid then
                humanoidCache[player] = humanoid
            end
            return humanoid
        end
    end
end

local MIN_Y = math.rad(-80)
local MAX_Y = math.rad(80)

local VR_ANGLE = math.rad(15)

local VR_LOW_INTENSITY_ROTATION = Vector2.new(math.rad(15), 0)
local VR_HIGH_INTENSITY_ROTATION = Vector2.new(math.rad(45), 0)
local VR_LOW_INTENSITY_REPEAT = 0.1
local VR_HIGH_INTENSITY_REPEAT = 0.4

local ZERO_VECTOR2 = Vector2.new(0, 0)
local ZERO_VECTOR3 = Vector3.new(0, 0, 0)

local TOUCH_SENSITIVTY = Vector2.new(math.pi*2.25, math.pi*2)
local MOUSE_SENSITIVITY = Vector2.new(math.pi*4, math.pi*1.9)

local MAX_TIME_FOR_DOUBLE_TAP = 1.5
local MAX_TAP_POS_DELTA = 15
local MAX_TAP_TIME_DELTA = 0.75

local SEAT_OFFSET = Vector3.new(0,5,0)
local VR_SEAT_OFFSET = Vector3.new(0, 4, 0)
local HEAD_OFFSET = Vector3.new(0, 1.5, 0)
local R15_HEAD_OFFSET = Vector3.new(0, 2.0, 0)

local PORTRAIT_MODE_CAMERA_OFFSET = 2

-- Reset the camera look vector when the camera is enabled for the first time
local SetCameraOnSpawn = true

local hasGameLoaded = false

local GestureArea = nil

--todo: remove this once TouchTapInWorld is on all platforms
local touchWorkspaceEventEnabled = pcall(function() local test = UserInputService.TouchTapInWorld end)

local function layoutGestureArea(portraitMode)
    if GestureArea then
        if portraitMode then
            GestureArea.Size = UDim2.new(1, 0, .6, 0)
            GestureArea.Position = UDim2.new(0, 0, 0, 0)
        else
            GestureArea.Size = UDim2.new(1, 0, .5, -18)
            GestureArea.Position = UDim2.new(0, 0, 0, 0)
        end
    end
end

-- Setup gesture area that camera uses while DynamicThumbstick is enabled
local function OnCharacterAdded(character)
    if UserInputService.TouchEnabled then
        if PlayerGui then
            local ScreenGui = Instance.new("ScreenGui")
            ScreenGui.Name = "GestureArea"
            ScreenGui.Parent = PlayerGui

            GestureArea = Instance.new("Frame")
            GestureArea.BackgroundTransparency = 1.0
            GestureArea.Visible = true
            GestureArea.BackgroundColor3 = Color3.fromRGB(0, 0, 0)
            layoutGestureArea(PortraitMode)
            GestureArea.Parent = ScreenGui

        end
        for _, child in ipairs(LocalPlayer.Character:GetChildren()) do
            if child:IsA("Tool") then
                IsAToolEquipped = true
            end
        end
        character.ChildAdded:Connect(function(child)
            if child:IsA("Tool") then
                IsAToolEquipped = true
            end
        end)
        character.ChildRemoved:Connect(function(child)
            if child:IsA("Tool") then
                IsAToolEquipped = false
            end
        end)
    end
end

if LocalPlayer then
    if LocalPlayer.Character ~= nil then
        OnCharacterAdded(LocalPlayer.Character)
    end
    LocalPlayer.CharacterAdded:connect(function(character)
        OnCharacterAdded(character)
    end)
end


local function positionIntersectsGuiObject(position, guiObject)
    if position.X < guiObject.AbsolutePosition.X + guiObject.AbsoluteSize.X
        and position.X > guiObject.AbsolutePosition.X
        and position.Y < guiObject.AbsolutePosition.Y + guiObject.AbsoluteSize.Y
        and position.Y > guiObject.AbsolutePosition.Y then
        return true
    end
    return false
end 

local function GetRenderCFrame(part)
    return part:GetRenderCFrame()
end

local function CreateCamera()
    local this = {}
    local R15HeadHeight = R15_HEAD_OFFSET
    function this:GetActivateValue()
        return 0.7
    end

    function this:IsPortraitMode()
        return PortraitMode
    end 

    function this:GetRotateAmountValue(vrRotationIntensity)
        vrRotationIntensity = vrRotationIntensity or StarterGui:GetCore("VRRotationIntensity")
        if vrRotationIntensity then
            if vrRotationIntensity == "Low" then
                return VR_LOW_INTENSITY_ROTATION
            elseif vrRotationIntensity == "High" then
                return VR_HIGH_INTENSITY_ROTATION
            end
        end
        return ZERO_VECTOR2
    end
    function this:GetRepeatDelayValue(vrRotationIntensity)
        vrRotationIntensity = vrRotationIntensity or StarterGui:GetCore("VRRotationIntensity")
        if vrRotationIntensity then
            if vrRotationIntensity == "Low" then
                return VR_LOW_INTENSITY_REPEAT
            elseif vrRotationIntensity == "High" then
                return VR_HIGH_INTENSITY_REPEAT
            end
        end
        return 0
    end

    local camMode = false
    UserInputService.InputBegan:connect(function(key)
        if key.KeyCode == Enum.KeyCode.E and camMode == false then
            this.ShiftLock = true
            camMode = true
        end
        if key.KeyCode == Enum.KeyCode.E and camMode == true then
            this.ShiftLock = false
            camMode = false
        end
    end)
    this.Enabled = false
    local isFirstPerson = false
    local isRightMouseDown = false
    local isMiddleMouseDown = false
    this.RotateInput = ZERO_VECTOR2
    this.DefaultZoom = LANDSCAPE_DEFAULT_ZOOM
    this.activeGamepad = nil

    local tweens = {}

    this.lastSubject = nil
    this.lastSubjectPosition = Vector3.new(0, 5, 0)

    local lastVRRotation = 0
    local vrRotateKeyCooldown = {}

    local isDynamicThumbstickEnabled = false

    -- Check for changes in ViewportSize to decide if PortraitMode
    local CameraChangedConn = nil
    local workspaceCameraChangedConn = nil
    local function onWorkspaceCameraChanged()
        if UserInputService.TouchEnabled then
            if CameraChangedConn then
                CameraChangedConn:Disconnect()
                CameraChangedConn = nil
            end
            local newCamera = workspace.CurrentCamera
            if newCamera then
                local size = newCamera.ViewportSize
                PortraitMode = size.X < size.Y
                layoutGestureArea(PortraitMode)
                DefaultZoom = PortraitMode and PORTRAIT_DEFAULT_ZOOM or LANDSCAPE_DEFAULT_ZOOM
                CameraChangedConn = newCamera:GetPropertyChangedSignal("ViewportSize"):Connect(function()
                    size = newCamera.ViewportSize
                    PortraitMode = size.X < size.Y
                    layoutGestureArea(PortraitMode)
                    DefaultZoom = PortraitMode and PORTRAIT_DEFAULT_ZOOM or LANDSCAPE_DEFAULT_ZOOM
                end)
            end
        end
    end
    workspaceCameraChangedConn = workspace:GetPropertyChangedSignal("CurrentCamera"):Connect(onWorkspaceCameraChanged)
    if workspace.CurrentCamera then
        onWorkspaceCameraChanged()
    end


    function this:GetShiftLock()
        return ShiftLockController:IsShiftLocked()
    end

    function this:GetHumanoid()
        local player = PlayersService.LocalPlayer
        return findPlayerHumanoid(player)
    end

    function this:GetHumanoidRootPart()
        local humanoid = this:GetHumanoid()
        return humanoid and humanoid.Torso
    end

    function this:GetRenderCFrame(part)
        GetRenderCFrame(part)
    end

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