How to use :Play() :Stop() in this script?

Sorry for so many questions about on key buttons but I think this is my last one. So I Have this script to make it so on "e", you will do the animation, the script is in starter pack and the animation is in starter pack.

local brick = workspace.brick
function lp()
    while bricfunction anim(key)
local key = key:lower()
if key == "e" then
script.Parent.Parent.Character.Humanoid:LoadAnimation(script.Parent.anim):Play() 
    wait()
    end
end
brick.Changed:connect(lp)
script.Parent.Parent:GetMouse().KeyDown:connect(anim)

This script seemed to work Sorry if that is wrong I retyped the script(couldn't copy and paste) I just dont know how you make it stop. I tried to use the same model and instead of :Play() I put :Stop() but that didn't work. So how would you make it so that if you click the same button (or a different one) it would stop?