SQLAlchemy如何在多对多关系中从关联表中获取列值

from sqlalchemy import create_engine, Column, Integer, String, Table, ForeignKey
from sqlalchemy.orm import relationship, sessionmaker
from sqlalchemy.ext.declarative import declarative_base

# 创建数据库引擎和会话
engine = create_engine('数据库连接字符串')
Session = sessionmaker(bind=engine)
session = Session()

# 创建基础模型
Base = declarative_base()

# 定义中间表
association_table = Table('association', Base.metadata,
    Column('left_id', Integer, ForeignKey('left_table.id')),
    Column('right_id', Integer, ForeignKey('right_table.id'))
)

# 定义左表模型
class LeftTable(Base):
    __tablename__ = 'left_table'
    id = Column(Integer, primary_key=True)
    name = Column(String)
    right_tables = relationship('RightTable', secondary=association_table, back_populates='left_tables')

# 定义右表模型
class RightTable(Base):
    __tablename__ = 'right_table'
    id = Column(Integer, primary_key=True)
    name = Column(String)
    left_tables = relationship('LeftTable', secondary=association_table, back_populates='right_tables')

# 查询多对多关系中的列值
left_table = session.query(LeftTable).filter_by(name='left_name').first()
for right_table in left_table.right_tables:
    print(right_table.name)