i have form with zip code and city, i m using api to find city by zip code when i enter the zip code i m calling api and i create city object if not in city object, but if is already in city objet will search just in city objet with zip code. my problem is in onchange when i write zip code i don't get directly result of api, onchange function works when i clique in some place of form, please any solution for that 

odoo 10