call function in loop

CREATE OR REPLACE FUNCTION get_all_ancestors()
RETURNS TABLE (
    c_id BIGINT,
    p_id BIGINT,
    p_type VARCHAR,
    pd_type VARCHAR,
    d_type VARCHAR,
    d_value VARCHAR
) AS
$BODY$
DECLARE
    r product_partition%ROWTYPE;
BEGIN
    FOR r IN
        SELECT * FROM product_partition WHERE partition_type = 'Unit'
    LOOP
        RETURN NEXT
            SELECT * product_partition_ancestors_fn(r.criterion_id, r.adgroup_id);
    END LOOP;
    RETURN;
END
$BODY$
LANGUAGE plpgsql;