riddle 2

what can be opened but never closed *this is the same answer btw if you want use it* what has to be opened before you use it *if ur malay use this one* dia ada kuning mata sama putih kepala masa campur kan dia jadi semua kuning apa dia? *srry i only know Malaysian malay and if it sound weird im not rlly good im malay reminder: its same answer for all bye toots*