#!/usr/bin/env python

import pickle
import StringIO

sio = StringIO.StringIO()
pickler = pickle.Pickler(sio)

class B(object):
    def __init__(self, name="unknown"):
        self.name = name
        self.a = None

    def setA(self, a):
        self.a = a

    def __reduce__(self):
        return self.__class__, (self.name,), self.__dict__

class A(object):
    def __init__(self, name, b):
        self.name = name
        self.b = b

    def __reduce__(self):
        return self.__class__, (self.name, self.b), self.__dict__

b = B("manny")
a = A("moe", b)
b.setA(a)

pickler.dump(a)