command /testgui [<player>] [<text>]:
    trigger:
        open chest with 1 row named "TESTOWEGUI" to player
        set player's current inventory's slot 1 to stone named "TEST"
        set {_gracz} to player
        set {_argument} to arg 1
        stop
       
on inventory click:
    if inventory name of player's current inventory is "TESTOWEEGUI":
        if clicked slot is 1:
            cancel event
            send "&7>> &cGRACZ: %{_gracz}%" to player
            send "&7>> &aARGUMENT: %{_argument}% to player