@Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;
        ZoneId zoneId = (ZoneId) o;
        return environment == zoneId.environment &&
               Objects.equals(region, zoneId.region);
    }
Returns the serialised value of this. Inverse of {@code ZoneId.from(String value)}.
config-provisioning/src/main/java/com/yahoo/config/provision/zone/ZoneId.java