def filter_cols(model, *filtered_columns):
    """Return columnsnames for a model except named ones.

    Useful for defer() for example to retain only columns of interest
    """
    m = sa.orm.class_mapper(model)
    return list(
        {p.key for p in m.iterate_properties if hasattr(p, "columns")}.difference(
            filtered_columns
        )
    )