text: from mongoengine.document import Document
  from mongoengine.fields import IntField, ReferenceField
  
  from app.models.model import Model
  from app.models.user import User
  
  default_params = {'required': True}
  default_string_params = {**default_params, 'max_length': 250}
  
  
  class DefaultModel(Document):
      user = ReferenceField(User)
      model = ReferenceField(Model)
      year = IntField(**default_params)
      meta = {
          'allow_inheritance': True,
          'abstract': True
      }
  