sqlalchemy mysql upserts insert or update

参考：https://docs.sqlalchemy.org/en/20/dialects/mysql.html#insert-on-duplicate-key-update-upsert

from sqlalchemy.dialects.mysql import insert
import models

insert_stmt = insert(models.KeyValue).values(
    key=lvkey,
    value=json.dumps(lvvalue),
    updatetime=datetime.datetime.now())
on_duplicate_key_stmt = insert_stmt.on_duplicate_key_update(
    value=insert_stmt.inserted.value,
    updatetime=insert_stmt.inserted.updatetime,
    status='U'
    )
db.session.execute(on_duplicate_key_stmt)
db.session.commit()