@classmethod
def add_quick_search_filter(cls, qs, search_text):
    """Add a filter to the given queryset `qs` in order to apply a quick
        search for the given `search_text`.

        """
    flt = qs.model.quick_search_filter(search_text)
    if len(flt) == 0:
        return qs.model.objects.none()
    return qs.filter(flt)
