[Python] How to parse ObjectId in a pydantic model?

I am trying to parse MongoDB records to a pydantic model but failing to do so for ObjectId

From what I understood, I need to setup validator for ObjectId and did try to both extend ObjectId class and add the validator decorator to my class using ObjectId. which I did as follows.

from pydantic import BaseModel, validator
from bson.objectid import ObjectId


class ObjectId(ObjectId):
pass
@classmethod
def __get_validators__(cls):
yield cls.validate
@classmethod
def validate(cls, v):
if not isinstance(v, ObjectId):
raise TypeError('ObjectId required')
return str(v)


class User(BaseModel):
who: ObjectId


class User1(BaseModel):
who: ObjectId
@validator('who')
def validate(cls, v):
if not isinstance(v, ObjectId):
raise TypeError('ObjectId required')
return str(v)

data = {"who":ObjectId('123456781234567812345678')}


Unfortunately, both "solution" are failing as follows:

>>> test = User(**data)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "pydantic/main.py", line 274, in pydantic.main.BaseModel.__init__
pydantic.error_wrappers.ValidationError: 1 validation error for User
id
field required (type=value_error.missing)


>>> test = User1(**data)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "pydantic/main.py", line 274, in pydantic.main.BaseModel.__init__
pydantic.error_wrappers.ValidationError: 1 validation error for User1
who
ObjectId required (type=type_error)


There is definitely something that I am missing here.

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