from django.db import models


class Register:
    REGISTRY = {}

    def __init__(self, name):
        self.name = name

    def __call__(self, cls):
        self.register(cls)
        return cls

    def register(self, cls):
        print(cls.__name__, '-', self.name)  # prints: Item - Item registered
        print(cls._meta.get_fields())  # raises: django.core.exceptions.AppRegistryNotReady: Models aren't loaded yet.


@Register('Item registered')
class Item(models.Model):
    title = models.CharField(max_length=200, verbose_name='Title')