presto-main/src/main/java/io/prestosql/connector/system/DelegatingSystemTablesProvider.java/DelegatingSystemTablesProvider/listSystemTables
class DelegatingSystemTablesProvider:    @Override
    public Set<SystemTable> listSystemTables(ConnectorSession session)
    {
        return delegates.stream()
                .flatMap(delegate -> delegate.listSystemTables(session).stream())
                .collect(toImmutableSet());
    }