from .Base import Base from datetime import datetime from sqlalchemy.orm import relationship from sqlalchemy import Column, Integer, String, DateTime class User(Base): __tablename__ = "users" id = Column(Integer, primary_key=True) email = Column(String(100), unique=True, nullable=False) password_hash = Column(String(256), nullable=False) created_at = Column(DateTime, default=datetime.now) conversations = relationship("Conversation", back_populates="user")