### Question:
ZergHosts { public ImmutableSet<ZergHost> toSet() { return hosts; } private  ZergHosts(ImmutableSet<ZergHost> hosts); static ZergHosts from(Collection<ZergHost> hosts); static @Nullable CassandraInstance toCassandraInstance(ZergHost host); ImmutableSet<String> rings(); ZergHosts filterRing(final String ring); ZergHosts filterRegion(final String region); ZergHosts filterScope(Map<String, String> ringScopes, String region, String ring); ImmutableSet<ZergHost> toSet(); ImmutableSet<CassandraInstance> toCassandraInstances();  }### Answer:
@Test public void toSet() { assertEquals(HOSTS, ZergHosts.from(HOSTS).toSet()); }