class Contingency extends AbstractExtendable<Contingency> {

    public static List<Contingency> checkValidity(List<Contingency> contingencies, Network network) {
        Objects.requireNonNull(contingencies);
        Objects.requireNonNull(network);
        return contingencies.stream()
                .filter(c -> isValid(c, network))
                .collect(Collectors.toList());
    }

    public  Contingency(String id, ContingencyElement... elements);
    public  Contingency(String id, List<ContingencyElement> elements);

}