Cant change mouse curser?

So, as you can tell by the code it's trying to change the mouse curser. However, studio says it's unable to change the curser.

The code is running on a local script in a Gui.

Code:

mhid = false
mouse = game.Players.LocalPlayer:GetMouse()
mouse.KeyDown:connect(function(key)
    key = string.lower(key)
    if string.byte(key) == 113 then
        if not mhid then
            mhid = true
            mouse.Icon = "http://www.roblox.com/asset/?id=20686724"
        elseif mhid then
            mhid = false
            mouse.Icon = ""
        end
    end
end)

Output: Cannot set Icon of a PlayerMouse