def test(store):
    from Book import Book

    b = Book()
    b.setTitle('foo')
    store.addObject(b)
    store.saveChanges()
    serialNum = b.serialNum()

    b = store.fetchObject(Book, serialNum)
    b.setTitle('bar')
    try:
        b = store.fetchObject(Book, serialNum)
    except AssertionError:
        # an assertion _should_ be generated, because we are attempting
        # to refresh a modified object.
        pass
    else:
        assert 0, 'Should have got an assertion failure, but none was raised.'
