function filter (obj) {
let keys = Object.keys(obj);
let key = keys.shift();
if (keys.length === 0) return obj;
if (!key.match(/_/gi)) {
return filter(obj[key]);
}
}
const obj = {
promo: {
koto: {
moto: 'sef',
_mlol: {
set: 'asd'
}
}
},
_moto: 'sef',
mlol: {
set: { _dodo: 'ts'}
}
}