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    <p>There is an <code>InheritanceManager</code> provided as part of <code>django-model-utils</code> which allows you to do this, see <a href="https://django-model-utils.readthedocs.org/en/latest/index.html" rel="nofollow noreferrer">docs</a>.</p> <p>To install in Linux / Mac:</p> <pre><code>sudo pip install django-model-utils </code></pre> <p>Annoyingly, installing using <code>easy_install</code> or <code>pip</code> on windows is not quite as straight forward, see: <a href="https://stackoverflow.com/questions/1449494/how-do-i-install-python-packages-on-windows">How do I install Python packages on Windows?</a>. A quick and dirty method is to download the <code>django-model-util/</code> directory from <a href="https://bitbucket.org/carljm/django-model-utils/src" rel="nofollow noreferrer">here</a> into the top directory of your django project, this is handy if you intend to copy the entire project across for deployment to a production webserver.</p> <p>In order to use the <code>InheritanceManager</code>, the models need to be refactored slightly:</p> <pre><code>from django.db import models from django.contrib.auth.models import User from datetime import datetime from model_utils.managers import InheritanceManager get_upload_file_name = 'images/' # I added this to debug models class BaseImage(models.Model): user = models.ForeignKey(User) image = models.ImageField(upload_to=get_upload_file_name) caption = models.CharField(max_length=200) pub_date = models.DateTimeField(default=datetime.now) objects = InheritanceManager() class BackgroundImage(BaseImage): pass class ProfilePicture(BaseImage): pass class Album(models.Model): user = models.ForeignKey(User) name = models.CharField(max_length=200) pub_date = models.DateTimeField(default=datetime.now) class Meta: ordering = ['-pub_date'] verbose_name_plural = ('Albums') def __unicode__(self): return self.name class Photo(BaseImage): album = models.ForeignKey(Album, default=3) </code></pre> <p>All the Image models now inherit from a common super class which creates an instance of the <code>InheritanceManager</code>. I've also moved up all the duplicated attributes into the superclass, but this isn't strictly necessary, using <code>InheritanceManager</code> means that any attributes which are not present in <code>BaseImage</code> can still be accessed in the template.</p> <p>To retrieve a list ordered by <code>-pubdate</code>:</p> <pre><code>BaseImage.objects.select_subclasses().order_by("-pub_date") </code></pre> <p>To use in a view:</p> <pre><code>def recentImages(request): r = BaseImage.objects.select_subclasses().order_by("-pub_date")[:20] return render_to_response("recentImages.html", { "imageList" : r }) </code></pre> <p>To use in a template:</p> <pre><code>{% for photo in imageList %} &lt;img src="{{ photo.image.url }}" /&gt; {% endfor %} </code></pre> <p>Is this something like what you are looking for?</p> <p><b>Edit</b></p> <p>The following code will still work fine, with the new models:</p> <pre><code>class UserProfile(models.Model): user = models.OneToOneField(User) permanent_address = models.TextField() temporary_address = models.TextField() profile_pic = models.ForeignKey(ProfilePicture) background_pic = models.ForeignKey(BackgroundImage) </code></pre> <p>Just make sure the names of the last two models in the <code>ForeignKey</code> relationship are correct!</p>
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    1. USHenry Florence
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    1. COThank you so much for the answer. This is what I was looking for. But just two more question though. Does django-model-utils work in windows, because I tried `pip install django-model-utils` but couldn't find it. And second, can I still use `ProfilePicture` and `BackgroundImage` in my `UserProfile` model (I have added in the edit the `UserProfile` model)?
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    2. CO@Aamu the ProfilePicture and BackgroundImage will behave exactly as before. I ve added a quick and dirty windows install method to the answer, there is also an alternative answer if this doesn't work.
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      1. USHenry Florence
    3. COI am sorry. At first I did was`django-models-utils` instead of django-model-utils`. Now its installed. And would you please be kind enough to answer me my second question, please.
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