static Cache<SS> cityToCountry_data = new Cache(func {
  L<SS> l = worldCitiesList();
  new SS data;
  for (SS line : l)
    putIfNotThere(data, toLower(line.get("name")), line.get("country"));
    
  // hotfix
  data.put("london", "United Kingdom");
  ret data;
});

static S cityToCountry(S city) {
  ret cityToCountry_data->get(toLower(city));
}