sqlalchemy 抛出sessionmaker' object has no attribute 'add'错误

Question

学习sqlalchemy的时候，按照文档写了一段代码

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

engine = create_engine('mysql+pymysql://test:123456@192.168.3.14:3306/tdb', echo=True)
Base = declarative_base()


class User(Base):
    __tablename__ = 'user'

    id = Column(Integer, autoincrement=True, primary_key=True, nullable=False)
    name = Column(String(64), unique=True, nullable=False)
    age = Column(Integer)

    def __str__(self):
        return 'User(id={}, name={}, age={})'.format(self.id, self.name, self.age)


Base.metadata.create_all(engine)

Session = sessionmaker(bind=engine)
session = Session
ins = User(name='Tom', age=20)
session.add(ins)
try:
    session.commit(ins)
except Exception as e:
    session.rollback()
    raise e

然后抛出了一个错误：

Traceback (most recent call last):
  File "/home/hysg/code/study/test/tdb.py", line 26, in <module>
    session.add(ins)
AttributeError: 'sessionmaker' object has no attribute 'add'

该如何修改代码？

Answer 1

session = Session()