* build multiple maps in series. Each map is a superset of the maps created before it.
   *
   * @since 2.0
   */
  public static class Builder<K, V> extends ImmutableMap.Builder<K, V> {
    private final Comparator<? super K> comparator;

    /**
     * Creates a new builder. The returned builder is equivalent to the builder generated by {@link
     * ImmutableSortedMap#orderedBy}.

    int expectedValuesPerKey = ImmutableCollection.Builder.DEFAULT_INITIAL_CAPACITY;

    /**
     * Creates a new builder. The returned builder is equivalent to the builder generated by {@link
     * ImmutableMultimap#builder}.
     */
    public Builder() {}

    /** Creates a new builder with a hint for the number of distinct keys. */
    Builder(int expectedKeys) {
      if (expectedKeys > 0) {

      "index" : {
        "creation_date" : "1509021057017",
        "number_of_shards" : "5",
        "number_of_replicas" : "1",
        "uuid" : "bhfc7WeARZymc_hr4dF1og",
        "version" : {
          "created" : "6000051"
        },
        "provided_name" : "fess_config.scheduled_job"
      }
    }
  }

    }

    /**
     * Creates a Type-3 message using default values from the current
     * environment.
     */
    public Type3Message() {
        setFlags(getDefaultFlags());
        setDomain(getDefaultDomain());
        setUser(getDefaultUser());
        setWorkstation(getDefaultWorkstation());
    }

    /**
     * Creates a Type-3 message in response to the given Type-2 message

    extends AbstractMapBasedMultiset<E> {

  /** Creates a new, empty {@code LinkedHashMultiset} using the default initial capacity. */
  public static <E extends @Nullable Object> LinkedHashMultiset<E> create() {
    return create(ObjectCountHashMap.DEFAULT_SIZE);
  }

  /**
   * Creates a new, empty {@code LinkedHashMultiset} with the specified expected number of distinct
   * elements.
   *

      "index" : {
        "creation_date" : "1509021060038",
        "number_of_shards" : "5",
        "number_of_replicas" : "1",
        "uuid" : "LRohRohXTCGxGdsabXPNnQ",
        "version" : {
          "created" : "6000051"
        },
        "provided_name" : "fess_log.favorite_log"
      }
    }
  }

		debug.PrintStack()
		return metacache{}
	}

	// Grab a write lock, since we create one if we cannot find one.
	b.mu.Lock()
	defer b.mu.Unlock()

	// Check if exists already.
	if c, ok := b.caches[o.ID]; ok {
		c.lastHandout = time.Now()
		b.caches[o.ID] = c
		b.debugf("returning existing %v", o.ID)
		return c
	}

	if !o.Create {
		return metacache{
			id:     o.ID,
			bucket: o.Bucket,

      "index" : {
        "creation_date" : "1509021049746",
        "number_of_shards" : "5",
        "number_of_replicas" : "1",
        "uuid" : "0xToIxg0R1KjZqA0ynv9PQ",
        "version" : {
          "created" : "6000051"
        },
        "provided_name" : "fess_config.bad_word"
      }
    }
  }

      "index" : {
        "creation_date" : "1509021056434",
        "number_of_shards" : "5",
        "number_of_replicas" : "1",
        "uuid" : "Zrp1Be7PS1ySzKAjlrpICg",
        "version" : {
          "created" : "6000051"
        },
        "provided_name" : "fess_config.request_header"
      }
    }
  }

	if err != nil {
		return nil, fmt.Errorf("failed creating kube client: %v", err)
	}

	return client, nil
}

// createHostsideProbeIpset creates an ipset. This is designed to be called from the host netns.
// Note that if the ipset already exist by name, Create will not return an error.
//
// We will unconditionally flush our set before use here, so it shouldn't matter.