[Python] Foreign key to the same table in Python Peewee

I am using ORM peewee for sqlite in Python. I would like to create table Item with field parent_id that will be foreign key to the Item:

from peewee import *

db = SqliteDatabase("data.db")

class Item(Model):
id = AutoField()
parent_id = ForeignKeyField(Item, null = True)

class Meta:
database = db

db.create_tables([Item])


However, there is error because of circular foreign key:

NameError: free variable 'Item' referenced before assignment in enclosing scope
​

For this case, there is DeferredForeignKey in peewee:

from peewee import *

db = SqliteDatabase("data.db")

class Item(Model):
id = AutoField()
parent_id = DeferredForeignKey("Item", null = True)

class Meta:
database = db

db.create_tables([Item])
Item._schema.create_foreign_key(Item.parent_id)


Unfortunately, there is no ADD CONSTRAINT in sqlite, so another error appears:

peewee.OperationalError: near "CONSTRAINT": syntax error
​

Is there any way to create circural foreign key in sqlite using peewee, or I have to use plain integer instead of foreign key or use native SQL instead of ORM?

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