Django admin - OneToOneField inline throws "ForeignKey exception"

I have a very simple application that currently declares two models, one is called "Content" and just contains the content data, and the other is "Page" which includes "Content" as OneToOneField.

The reason I did this is because I can have "Page" as a specific concrete class that I am using, and when other models in other modules I plan to need page data, they can just include "Content" like OneToOneField. I did it this way to avoid inheritance and use composition.

models.py:

from django.db import models

class Content(models.Model):
    """Basic page data which can be used by other modules"""
    title = models.CharField(max_length=200)
    html_title = models.CharField(max_length=200)
    meta_desc = models.CharField(max_length=200)
    keywords = models.CharField(max_length=200)
    content = models.TextField()

class Page(models.Model):
    """Concrete implementation of a basic page managed by the admin"""
    slug = models.SlugField()
    content = models.OneToOneField(Content)

    def __str__(self):
        return self.content.title

      

        
        
        
      

    

admin.py:

from django.contrib import admin
from content.models import Page, Content

class ContentInline(admin.TabularInline):
    model = Content
    fields = ('title', 'html_title', 'meta_desc', 'keywords', 'content')

class PageAdmin(admin.ModelAdmin):
    fields = ('slug',)
    inlines = [ContentInline]

      

        
        
        
      

    

On the admin page I am getting this exception:

Exception at /admin/content/page/add/
<class 'content.models.Content'> has no ForeignKey to <class 'content.models.Page'>

      

        
        
        
      

    

What says is of course correct, but I can't seem to find a way to do what I want, which is to include the inline side of the non-defining side of the relationship. I do not want to declare a relationship in "Content", since then I will need to define each relationship to it within this class, which will inject dependencies to other modules, which, in my opinion, should not know anything.

Using Django 1.6 in Python 3.3.

Edit: As pointed out in the comments, I decided to use inheritance. My first concern with this was that I wanted the flexibility to be able to compose classes from several other classes. However, since the Django ORM supports multiple inheritance, and if I realized this method is called "mixins" (new to Python), I would have gotten somewhere much sooner.

Example mixins with models:

from django.db import models

class Content(models.Model):
    """Basic page data which can be used by other modules"""
    title = models.CharField(max_length=200)
    html_title = models.CharField(max_length=200)
    meta_desc = models.CharField(max_length=200)
    keywords = models.CharField(max_length=200)
    content = models.TextField()

    def __str__(self):
        return self.title

    class Meta:
        abstract = True

class Data(models.Model):
    data_name = models.CharField(max_length=200)

    class Meta:
        abstract = True

class Page(Content, Data):
    """Concrete implementation of a basic page managed by the admin"""
    slug = models.SlugField()

      

        
        
        
      

    

And then I can just use it as one model in admin.py.