def METHOD_NAME(querysets, users, date_range):
    """Of the group ``users``, count how many made a contribution in ``date_range``."""
    start, end = date_range
    retained_users = set()
    for queryset, fields in querysets:
        for field in fields:
            filters = {"%s__in" % field: users, "created__gte": start, "created__lt": end}
            retained_users |= set(getattr(o, field) for o in queryset.filter(**filters))
    return len(retained_users)