python sqlalchemy orm

from sqlalchemy import *
from sqlalchemy.orm import Session
from sqlalchemy.ext.automap import automap_base
from sqlalchemy.orm.session import make_transient
from sqlalchemy.orm import load_only

connect_string = "mssql+pymssql://user:pass@url:3433/dbname?charset=utf8"
# sqlserver 

# mysql
engine = create_engine('mysql+pymysql://root:111@10.254.20.185/monitor?charset=utf8', echo=False)
metadata_r = MetaData()
metadata_r.reflect(engine, only=['comp_info'])
Base_r = automap_base(metadata=metadata_r)
Base_r.prepare()
comp_info = Base_r.classes.comp_info
session = Session(engine)
res = session.query(comp_info).filter(comp_info.flag == message).all()