pawl

from collections import defaultdict

from sqlalchemy import create_engine, Column, ForeignKey, Integer
from sqlalchemy.orm import relationship, scoped_session, sessionmaker
from sqlalchemy.orm.attributes import set_committed_value
from sqlalchemy.ext.declarative import declarative_base

engine = create_engine('mysql://root@localhost/test?charset=utf8mb4',
                       convert_unicode=True,
                       echo=True)