Is it possible to check if a player is holding down a key? (SOLVED)

In a local script:

local player = game.Players.LocalPlayer
local mouse = player:GetMouse()

local down = {}

mouse.KeyDown:connect(function(key)
    --'tag' the time the key was pressed, set pressing to true
    down[key:lower()] = {pressing = true, tag = tick()}
end)

mouse.KeyUp:connect(function(key)
    --set pressing to false
    down[key:lower()] = {pressing = false, tag = 0}
end)

game:GetService("RunService").RenderStepped:connect(function()
    --loop through the keys
    for key, array in pairs(down) do
        --if the key is being pressed
        if array.pressing then
            print("\"" .. key .. "\" has been held for " .. tick() - array.tag .. " seconds.")
            if tick() - array.tag > 5 then
                print("ALERT: \"" .. key .. "\" has been held for more than 5 seconds!")    
            end
        end
    end
end)

Not very flexible and it can't tell if you let go and then re-held the key within the 5 seconds but it works...

local Key=nil
function KeyDown(K)
    Key=K
    wait(5)
    if Key then
        print(Key.." was held for 5 seconds")
    end
end
function KeyUp()
    Key=nil
end