old_contents: from __future__ import unicode_literals
  
  from copy import copy
  
  from django.contrib import admin
  from django.contrib.admin.views.main import ChangeList
  
  from .forms import *
  from .settings import *
  from .abstract_models import to_search
  from .loading import get_cities_models
  
  Country, Region, City = get_cities_models()
  
  
  class CountryAdmin(admin.ModelAdmin):
      """
      ModelAdmin for Country.
      """
  
      list_display = (
          'name',
          'code2',
          'code3',
          'continent',
          'tld',
          'phone',
          'geoname_id',
      )
      search_fields = (
          'name',
          'name_ascii',
          'code2',
          'code3',
          'tld',
          'geoname_id',
      )
      list_filter = (
          'continent',
      )
      form = CountryForm
  
  
  admin.site.register(Country, CountryAdmin)
  
  
  class RegionAdmin(admin.ModelAdmin):
      """
      ModelAdmin for Region.
      """
      list_filter = (
          'country__continent',
          'country',
      )
      search_fields = (
          'name',
          'name_ascii',
          'geoname_id',
      )
      list_display = (
          'name',
          'country',
          'geoname_id',
      )
      form = RegionForm
  
  
  admin.site.register(Region, RegionAdmin)
  
  
  class CityChangeList(ChangeList):
      def get_query_set(self, request):
          if 'q' in list(request.GET.keys()):
              request.GET = copy(request.GET)
              request.GET['q'] = to_search(request.GET['q'])
          return super(CityChangeList, self).get_query_set(request)
  
  
  class CityAdmin(admin.ModelAdmin):
      """
      ModelAdmin for City.
      """
      list_display = (
          'name',
          'region',
          'country',
          'geoname_id',
      )
      search_fields = (
          'search_names',
          'geoname_id',
      )
      list_filter = (
          'country__continent',
          'country',
      )
      form = CityForm
  
      def get_changelist(self, request, **kwargs):
          return CityChangeList
  
  
  admin.site.register(City, CityAdmin)
  
new_contents: from __future__ import unicode_literals
  
  from copy import copy
  
  from django.contrib import admin
  from django.contrib.admin.views.main import ChangeList
  
  from .forms import *
  from .settings import *
  from .abstract_models import to_search
  from .loading import get_cities_models
  
  Country, Region, City = get_cities_models()
  
  
  class CountryAdmin(admin.ModelAdmin):
      """
      ModelAdmin for Country.
      """
  
      list_display = (
          'name',
          'code2',
          'code3',
          'continent',
          'tld',
          'phone',
          'geoname_id',
      )
      search_fields = (
          'name',
          'name_ascii',
          'code2',
          'code3',
          'tld',
          'geoname_id',
      )
      list_filter = (
          'continent',
      )
      form = CountryForm
  
  
  admin.site.register(Country, CountryAdmin)
  
  
  class RegionAdmin(admin.ModelAdmin):
      """
      ModelAdmin for Region.
      """
      list_filter = (
          'country__continent',
          'country',
      )
      search_fields = (
          'name',
          'name_ascii',
          'geoname_id',
      )
      list_display = (
          'name',
          'country',
          'geoname_id',
      )
      form = RegionForm
  
  
  admin.site.register(Region, RegionAdmin)
  
  
  class CityChangeList(ChangeList):
      def get_query_set(self, request):
          if 'q' in list(request.GET.keys()):
              request.GET = copy(request.GET)
              request.GET['q'] = to_search(request.GET['q'])
          return super(CityChangeList, self).get_query_set(request)
  
  
  class CityAdmin(admin.ModelAdmin):
      """
      ModelAdmin for City.
      """
      list_display = (
          'name',
          'region',
          'country',
          'geoname_id',
          'timezone'
      )
      search_fields = (
          'search_names',
          'geoname_id',
          'timezone'
      )
      list_filter = (
          'country__continent',
          'country',
          'timezone'
      )
      form = CityForm
  
      def get_changelist(self, request, **kwargs):
          return CityChangeList
  
  
  admin.site.register(City, CityAdmin)
  
subject: Add timezone field to CityAdmin.