String id = getId(system);
State state = system.getStates().get(acronym);
if(system.getCities().get(id) == null){
City city = new City(id, cityName, state);
system.getCities().put(id, city);
}
if(!isCityExistsInState(system.getCities().get(id), state)) {
state.addCity(system.getCities().get(id));