@Override
    public List<InetSocketAddress> getPeers(long services, Duration timeout) {
        if (services != 0)
            log.info("Pre-determined peers cannot be filtered by services: {}", services);
        return Collections.unmodifiableList(seedAddrs);
    }
@Test
    public void getPeers_length() throws Exception{
        SeedPeers seedPeers = new SeedPeers(MAINNET);
        List<InetSocketAddress> addresses = seedPeers.getPeers(0, Duration.ZERO);
        assertThat(addresses.size(), equalTo(MAINNET.getAddrSeeds().length));
    }