def get_event_poster_url(event):
    """Returns poster url of given event."""

    event_poster_url = None

    poster_div = event.find('div', class_="js-product-img")
    event_poster_url = poster_div.get("data-original")

    if not event_poster_url:
        poster_div = event.find('div', class_="t778__bgimg")
        event_poster_url = poster_div.get("data-original")

    return event_poster_url