Postgresql delete all table in a scheme exclude 'spatial_ref_sys'

deleta_all.sql

DO $$ DECLARE
    r RECORD;
BEGIN
    FOR r IN (SELECT tablename FROM pg_tables WHERE (schemaname = current_schema() and tablename != 'spatial_ref_sys')) LOOP
        EXECUTE 'DROP TABLE IF EXISTS ' || quote_ident(r.tablename) || ' CASCADE';
    END LOOP;
END $$;