Toggle GUI Visibility on key press. (Meaningless Question mark ?)

How would I make it so when a key is pressed the, GUI is visible to whoever pressed the button.

In a localscript do:

local uis = game:GetService("UserInputService")

local gui = script.Parent --// Define the gui

local open = false

uis.InputBegan:Connect(function(key)
	if key == Enum.KeyCode.K and not open then
		gui.Enabled = true
		open = true
	elseif key == Enum.KeyCode.K and open then
		gui.Enabled = false
		open = false
	end
end)

Accept answer if it works else tell me