dataLayer.push({ ecommerce: null });
dataLayer.push({
    event: 'begin_checkout',
    ecommerce: {
        items: [
            {
                item_id: 'COURSE_24',
                item_name: 'bellicon\u0020INTERVALL\u0020Workshop',
                currency: 'USD',
                price: 175,
                quantity: 1
            }
        ]
    }
});