    public Event getEventDetails() {
        throw new AssertionError("This method should not be called.");
    }

    @Override
    public void updateFilteredPersonList(Predicate<Person> predicate) {
        throw new AssertionError("This method should not be called.");
    }

    @Override
    public boolean canUndoAddressBook() {
        throw new AssertionError("This method should not be called.");