__init__.py 文件源码

def get_node_class_for_model(model, for_concrete_model=True):
    """
    Model nodes represent a model instance in the database.
    :param model: Django model class.
    :returns: A ``ModelNode`` class.
    """
    if for_concrete_model:
        model = model._meta.concrete_model

    if model in __node_cache__:
        return __node_cache__[model]
    else:
        @six.add_metaclass(ModelNodeMeta)
        class ModelNode(ModelNodeMixin, StructuredNode):
            __metaclass_model__ = model

            class Meta:
                model = None  # Will pick model from parent class __metaclass_model__ attribute

        __node_cache__[model] = ModelNode
        return ModelNode