I can't use computed and pydantic_model_creator properly.

[KAMRON-DEVELOPER]

I just wanted to add followers_count and followings_count to response when calling model_dump() or model_dump_json().

# users_app/test.py

ProfilePydantic = pydantic_model_creator(cls=UserModel)

@users_router.get(path="/test-user-response-model")
async def test_user_response_model():
    try:
        model: Optional[UserModel] = await UserModel.get_or_none(
            username="atajanov_kamronbek",
            password="@kamronbek2003",
        ).prefetch_related("followers", "followings")

        pydantic_model = await ProfilePydantic.from_tortoise_orm(obj=model)

        print(f"pydantic_model.model_dump_json: {pydantic_model.model_dump()}")

        return pydantic_model.model_dump_json()
    except Exception as e:
        my_logger.error(f"Exception e: {e}")
        raise HTTPException(status_code=400, detail=f"Internal Server Error e: {e}")

# users_app/models.py

class UserModel(BaseModel):
    first_name = fields.CharField(max_length=50, null=True)
    last_name = fields.CharField(max_length=50, null=True)
    username = fields.CharField(max_length=50, unique=True)
    email = fields.CharField(max_length=50, unique=True)
    phone_number = fields.CharField(max_length=50, unique=True, null=True)
    password = fields.CharField(max_length=255)

    followers: fields.ReverseRelation["FollowModel"]
    followings: fields.ReverseRelation["FollowModel"]

    class Meta:
        table = "user_model"

    def followers_count(self) -> int:
        try:
            return len(self.followers)
        except NoValuesFetched:
            return -1

    def followings_count(self) -> int:
        try:
            return len(self.followings)
        except NoValuesFetched:
            return -1

    class PydanticMeta:
        exclude = ["password"]
        computed = ("followers_count", "followings_count")

class FollowModel(BaseModel):
    follower: fields.ForeignKeyRelation["UserModel"] = fields.ForeignKeyField(model_name="users_app.UserModel", related_name="followings", to_field="id")
    following: fields.ForeignKeyRelation["UserModel"] = fields.ForeignKeyField(model_name="users_app.UserModel", related_name="followers", to_field="id")
    follow_status: FollowStatus = fields.CharEnumField(enum_type=FollowStatus, default=FollowStatus.ACCEPTED)

    class Meta:
        table = "follow_model"
        unique_together = ("follower", "following")

# console error log

(pod/apps/users_app/test.py)    🌋 Exception e: 'apps.users_app.models.UserModel:gbjuu5' object has no attribute 'followers'
INFO:     127.0.0.1:41028 - "GET /api/v1/users/test-user-response-model HTTP/1.1" 400 Bad Request
WARNING:  WatchFiles detected changes in 'apps/users_app/models.py'. Reloading...
INFO:     Shutting down
INFO:     Waiting for application shutdown.
INFO:     Application shutdown complete.

[waketzheng]

For compute field, you have to explicit init model before create the pydantic model class:

tortoise-orm/examples/pydantic/tutorial_4.py

Line 81 in 503c93b

Tortoise.init_models(["__main__"], "models")

There are several examples for pydantic.
And welcome to make PR if you have new example to share.