test

import  sqlalchemy
from  sqlalchemy.orm  import  relation, backref, sessionmaker
from  sqlalchemy.ext.declarative  import  declarative_base
from  sqlalchemy  import  Column, Integer, String, ForeignKey
engine  =  sqlalchemy.create_engine( ' sqlite:///:memory: ' , echo = True)
Base  =  declarative_base()
session  =  sessionmaker(bind = engine)()

class  Address(Base):
     __tablename__   =   ' addresses '
    id  =  Column(Integer, primary_key = True)
    content  =  Column(String)
    user_id  =  Column(Integer, sqlalchemy.ForeignKey( ' users.id ' ))

     def   __init__ (self, user, content):
        self.user  =  user
        self.content  =  content
     def   __repr__ (self):
         return   " <Address('%s')> "   %  self.content

    
class  User(Base):
     __tablename__   =   ' users '
    id  =  Column(Integer, primary_key = True)
    name  =  Column(String)
    comment  =  Column(String)
    addresses  =  relation( ' Address ' , order_by = ' Address.id ' , backref = ' user ' )
     def   __init__ (self, name, comment):
        self.name  =  name
        self.comment  =  comment
     def   __repr__ (self):
         return   " <User('%s', '%s')> "   %  (self.name, self.comment)

    
class  Photo(Base):
     __tablename__   =   ' photos '
    id  =  Column(Integer, primary_key = True)
    name  =  Column(String)
    user_id  =  Column(Integer, ForeignKey( ' users.id ' ))
    user  =  relation( ' User ' , backref = backref( ' photos ' ))
     def   __init__ (self, user, name):
        self.user  =  user
        self.name  =  name
     def   __repr__ (self):
         return   " <Photo('%s')> "   %  self.name
        
Base.metadata.create_all(bind = engine)