from datetime import datetime from typing import Optional, TYPE_CHECKING from sqlmodel import Field, Relationship from learn_sql_model.models.fast_model import FastModel if TYPE_CHECKING: from learn_sql_model.models.hero import Hero class Pet(FastModel, table=True): id: Optional[int] = Field(default=None, primary_key=True) name: str = "Jim" birthday: Optional[datetime] = None hero: "Hero" = Relationship(back_populates="pet")