@classmethod
def ads_for(cls, date, include_in_newsletter=False, show_on_website=False):
    """Return the ads for `date`, for newsletter or website or both.
        """
    ads = cls.objects.all()
    if include_in_newsletter:
        ads.filter(include_in_newsletter=True)
    if show_on_website:
        ads.filter(show_on_website=True)
    ads = ads.filter(start__lte=date).filter(end__gte=date).order_by(
        'display_weight')
    return ads
