它没有安装或是抽象的

Question

class Journal(models.Model):
    user = models.ForeignKey('mysite.apps.person.models.Person', related_name="user_journals")

但我得到了：

.. has 'user' relation with Model "mysite.apps.person.models.Person", which has either not been installed or is abstract

在settings.py

中

INSTALLED_APPS = (
    ...
    'mysite.apps.person',
    ...
)

我做错了什么？