from pydantic import BaseModel from datetime import datetime from typing import Optional class ItemBase(BaseModel): name: str description: Optional[str] = None is_active: bool = True class ItemCreate(ItemBase): pass class ItemUpdate(BaseModel): name: Optional[str] = None description: Optional[str] = None is_active: Optional[bool] = None class Item(ItemBase): id: int created_at: datetime updated_at: Optional[datetime] = None class Config: from_attributes = True