[Python] Why am I getting 'type[Category] instead of Category?

I'm playing with FastAIPI/sqlalchemy. Repository is working correctly, I can CRUD from swagger and everything is being displayed in .sqlite file. Problem I have is that methods that return fetched item from db (read_one, update_one and delete_one), shows warning on return value "Expected type 'Category', got 'type[Category]' instead".

from dataclasses import dataclass
from typing import Sequence

from sqlalchemy import select
from sqlalchemy.orm import Session

from app.models.coordinate import Category
from app.repositories.errors import DoesNotExistError, ExistError
from app.repositories.model import Repository
from app.schemas.coordinates import CategoryCreate, CategoryUpdate


@dataclass(frozen=True)
class CategorySqliteRepository(
Repository[
Category,
CategoryCreate,
CategoryUpdate,
]
):
sqlite: Session

def read_one(self, item_id: int) -> Category:
category = self.sqlite.get(Category, item_id)

if category is None:
raise DoesNotExistError(resource="category", id=str(item_id))

return category

def read_all(self, skip: int = 0, limit: int = 100) -> Sequence[Category]:
return self.sqlite.scalars(select(Category).offset(skip).limit(limit)).all()

def create_one(self, item: CategoryCreate) -> Category:
data = item.model_dump()
category = Category(**data)

existing_category = self.sqlite.scalars(
select(Category).filter(Category.name == category.name)
).all()
if existing_category:
raise ExistError(resource="category", name=category.name)

self.sqlite.add(category)
self.sqlite.commit()
self.sqlite.refresh(category)

return category

def update_one(self, item_id: int, item: CategoryUpdate) -> Category:
category = self.sqlite.get(Category, item_id)

if category is None:
raise DoesNotExistError(resource="category", id=str(item_id))

data = item.model_dump(exclude_unset=True)
existing_category = self.sqlite.scalars(
select(Category).filter(Category.name == data["name"])
).all()
if existing_category:
raise ExistError(resource="category", name=data["name"])

for key, value in data.items():
setattr(category, key, value)
self.sqlite.add(category)
self.sqlite.commit()
self.sqlite.refresh(category)

return category

def delete_one(self, item_id: int) -> Category:
category = self.sqlite.get(Category, item_id)

if category is None:
raise DoesNotExistError(resource="category", id=str(item_id))

self.sqlite.delete(category)
self.sqlite.commit()

return category



from typing import List

from sqlalchemy import ForeignKey, Integer, String
from sqlalchemy.orm import (
Mapped,
mapped_column,
relationship,
)

from app.runner.database import Base


class Category(Base):
__tablename__ = "category"

id: Mapped[int] = mapped_column(Integer, primary_key=True)
name: Mapped[str] = mapped_column(String, unique=True, nullable=False)

coordinates: Mapped[List["Coordinate"]] = relationship(
back_populates="category", cascade="all, delete-orphan"
)



from pydantic import BaseModel, ConfigDict


class CategoryBase(BaseModel):
model_config = ConfigDict(from_attributes=True)

name: str


class CategoryCreate(CategoryBase):
pass


class CategoryPublic(CategoryBase):
id: int


class CategoryUpdate(BaseModel):
name: str | None = None


class CoordinatePublicWithCategory(CoordinatePublic):
model_config = ConfigDict(from_attributes=True)

category: CategoryPublic | None = None


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