text: from django.db import models
  from jsonfield import JSONField
  from typing import Any
  
  DEFAULT_TEKVAT_RATE_TYPES_INSTANCE_ID = 1
  
  
  class TekvatVat(models.Model):
      country_code = models.CharField(max_length=3, db_index=True)
      data = JSONField()
  
  
  class TekvatRateTypeQuerySet(models.QuerySet):
      def default_instance(self):
          return self.filter(id=DEFAULT_TEKVAT_RATE_TYPES_INSTANCE_ID).first()
  
  
  class TekvatRateType(models.Model):
      data = JSONField()
  
      objects = TekvatRateTypeQuerySet.as_manager()
  
  