def repr_class_data(self, class_data):
        """Create code like this::
        
            class Person(classtree.Base):
                def __init__(self, name=None, person_id=None):
                    self.name = name
                    self.person_id = person_id
            
            
            class PersonCollection(classtree.Base):
                def __init__(self, collection_id=None, create_date=None, name=None):
                    self.collection_id = collection_id
                    self.create_date = create_date
                    self.name = name
            
                    person = Person(name='Jack', person_id=1)
                    self.name____Jack = person
                    self.person_id____1 = person
                    
                    person = Person(name='Paul', person_id=2)
                    self.name____Paul = person
                    self.person_id____2 = person
        """
        if "subclass" in class_data:
            for subclass_data in class_data["subclass"]:
                self.repr_class_data(subclass_data)
        self.repr_def_class(class_data)
        self.repr_setattr(class_data)