кусок данных из файла "Все города мира с часовым поясом" (22mb, ~900 000 lines)

gistfile1.txt

 {
   "geoname_id": 458695,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "",
   "city_name": "Коцены",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 458880,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "",
   "city_name": "Кекава",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 458892,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "",
   "city_name": "Кегумс",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 458910,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "",
   "city_name": "",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 458972,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "",
   "city_name": "Карсава",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 459004,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "",
   "city_name": "",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 459031,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "",
   "city_name": "Кандава",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 459201,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "",
   "city_name": "Юрмала",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 459220,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "",
   "city_name": "",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 459279,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "Елгава",
   "city_name": "Елгава",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 459283,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "Екабпилсский край",
   "city_name": "Екабпилс",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 459359,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "",
   "city_name": "",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 459363,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "",
   "city_name": "",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 459365,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "",
   "city_name": "",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 459379,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "",
   "city_name": "Posëlok Marupe",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 459402,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "",
   "city_name": "Яунелгава",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 459563,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "",
   "city_name": "Инчукалнс",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 459564,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "",
   "city_name": "Инциемс",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 459585,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "Даугавпилсский край",
   "city_name": "",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 459598,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "",
   "city_name": "Икшкиле",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 459624,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "",
   "city_name": "Иецава",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 459668,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "",
   "city_name": "Гулбене",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 459680,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "",
   "city_name": "",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 459692,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "",
   "city_name": "",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 459842,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "",
   "city_name": "",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 459871,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "",
   "city_name": "",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 459985,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "",
   "city_name": "",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 460001,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "",
   "city_name": "Эргли",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 460019,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "",
   "city_name": "",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 460046,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "",
   "city_name": "",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 460142,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "",
   "city_name": "",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 460187,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "",
   "city_name": "",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 460235,
   "country_iso_code": "LV",
   "country_name": "Латвия",
   "region_name": "",
   "city_name": "Друвиена",
   "time_zone": "Europe/Riga"
 },
 {
   "geoname_id": 460243,
   "country_iso_code": "LV",
   "country_name": "Латвия",