fetch json

const config = {
    wk_items: {
        options: {subjects: true, assignments: true},
        filters: {
            item_type: 'kan'
        }
    }
};

wkof.ItemData.get_items(config).then((data) => {
    const kanjiArray = [];
    data.forEach((kanjiData) => {
        kanjiArray.push(kanjiData.data.characters);
    })
    const kanjiJSON = JSON.stringify(kanjiArray);
    console.log(JSON.stringify(kanjiJSON));
})