SQLAlchemy 访问Mysql数据库弹出Warning,VARIABLE_VALUE，如何解决？

Question

1.写了一段使用SQLAlchemy 编程的代码，程序本身没问题，就是访问数据库时产生一个错误提示，但是即使有错误代码页能正常运行，操作结果也正确。这个错误是关于代码编码方式的错误，但是调了很长时间这个错误就是不能消除，求解救

2.这里是代码：（1）orm.py

---

from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy import Column,Integer,String
Base = declarative_base()
class Account(Base):
    __tablename__ = u'account'
    id = Column(Integer,primary_key = True)
    salary = Column(Integer)
    username = Column(String(20),nullable = False)
    password = Column(String(200),nullable = False)
    title  = Column(String(50))
    
    def is_active(self):
        return True
    def get_id(self):
        return self.id
    def is_authenticated(self):
        return True
    def is_anonymous(self):
        return False
from sqlalchemy import create_engine
from sqlalchemy.orm import scoped_session,sessionmaker
db_connect_string = 'mysql://root:admin@localhost:3306/test_database?charset=utf8'
ssl_args = {'ssl':{'cert':'/home//ssl/client-cert.pem',
            'key':"/home/shouse/ssl/client-cert.pem",
            'ca':'/home/shouse/ssl/ca-cert.pem'}}
engine = create_engine(db_connect_string,connect_args = ssl_args)
SessionType = scoped_session(sessionmaker(bind = engine,expire_on_commit = False))
def GetSession():
    return SessionType()
from contextlib import contextmanager
@contextmanager
def session_scope():
    session = GetSession()
    try:
        yield session
        session.commit()
    except:
        session.rollback()
        raise
    finally:
        session.close()

（2）databaseoperation.py代码：

# -*- coding:utf-8 -*-
import orm
from sqlalchemy import or_
def InsertAccount(user,password,title,salary):
    with orm.session_scope() as session:
        account = orm.Account(username = user,password =password,title = title,salary = salary)
        session.add(account)
def GetAccount(id=None,username = None):
    with orm.session_scope() as session:
        return session.query(orm.Account).filter(or_(orm.Account.id==id,orm.Account.username==username)).first()
def Delete(username):
    with orm.session_scope() as session:
        account = GetAccount(username = username)    
        if account:
            session.delete(account)
def Update(id,username,password,title,salary):
    with orm.session_scope() as session:
        account = session.query(orm.Account).filter(orm.Account.id==id).first()
        if not account:return
        account.username=username
        account.password=password
        account.title = title
        account.salary = salary

InsertAccount('Lliy','123','System Manager',3000)
InsertAccount('Rebeca Li','12221','Accountant',3000)

GetAccount(2)

Delete('David Li')
Update(1,'admin','1111','System Admin',2000)

3.错误提示：

4.数据库截图

Answer 1

这是一个警告Warning，而不是错误Error，但是不知道触发那种机制导致代码反馈这种警告Warning