def _boolean_stats(model, filtering, field_names):
    """Get stats for boolean fields for any service class."""
    boolean_stats = []
    for fname in field_names:
        title = model._meta.get_field(fname).verbose_name.__unicode__()
        filtering_bln = {fname: True}
        filtering_bln.update(filtering)
        cnt = model.objects.filter(**filtering_bln).count()
        boolean_stats.append((title, cnt))
    return tuple(boolean_stats)