old_contents: from django.core.management import BaseCommand
  from django_pyowm.models import Location
  from pyowm.webapi25.location import Location as LocationEntity
  
  from weather_api.weather.singletons import owm
  
  
  class Command(BaseCommand):
      help = 'Save all locations from file to database'
  
      def handle(self, *args, **options):
          if Location.objects.exists():
              self.stderr.write('You can save locations only to empty table')
              return
  
          city_registry = owm.city_id_registry()
          locations = []
          for line in city_registry._get_all_lines():
              tokens = line.strip().split(',')
              try:
                  location_entity = LocationEntity(tokens[0], float(tokens[3]), float(tokens[2]), int(tokens[1]), tokens[4])
                  location = Location.from_entity(location_entity)
                  locations.append(location)
              except ValueError:
                  pass
          Location.objects.bulk_create(locations, 10000)
          self.stdout.write(self.style.SUCCESS('{} locations saved to database'.format(len(locations))))
  
new_contents: from django.core.management import BaseCommand
  from django_pyowm.models import Location
  from pyowm.webapi25.location import Location as LocationEntity
  
  from weather_api.weather.singletons import owm
  
  
  class Command(BaseCommand):
      help = 'Save all locations from file to database'
  
      def handle(self, *args, **options):
          if Location.objects.exists():
              self.stderr.write('You can save locations only to empty table')
              return
  
          city_registry = owm.city_id_registry()
          locations = []
          for line in city_registry._get_all_lines():
              tokens = line.strip().split(',')
              try:
                  location_entity = LocationEntity(tokens[0], float(tokens[3]), float(tokens[2]), int(tokens[1]), tokens[4])
                  location = Location.from_entity(location_entity)
                  locations.append(location)
              except ValueError:
                  pass
          Location.objects.bulk_create(locations, 500)
          self.stdout.write(self.style.SUCCESS('{} locations saved to database'.format(len(locations))))
  
subject: Make batch less, because sqlite cannot handle big batches