title: Django "ValueError: Can't bulk create a multi-table inherited model"
body: <h3>Problem</h3>
  <p>I am using the django-model-utils InheritanceManager. I have a super Notification(models.Model) class which I use to create many notification subclasses such as <code>PostNotification(Notification)</code>, <code>CommentNotification(Notification)</code>, etc., and when trying to run <code>CommentNotification.objects.bulk_create(list_of_comment_notification_objects)</code>, i get the following traceback:</p>
  <pre><code>File &quot;/home/me/.virtualenvs/project/local/lib/python2.7/site-packages/django/db/models/query.py&quot;, line 429, in bulk_create
      raise ValueError(&quot;Can't bulk create a multi-table inherited model&quot;)
  ValueError: Can't bulk create a multi-table inherited model
  </code></pre>
  <p>and upon inspecting the query.py file, we get this causes the error:</p>
  <pre><code>for parent in self.model._meta.get_parent_list():
        if parent._meta.concrete_model is not self.model._meta.concrete_model:
             raise ValueError(&quot;Can't bulk create a multi-table inherited model&quot;)
  </code></pre>
  <p>Environment
  Django Model Utils version: 3.1.1
  Django version: 1.11.7
  Python version: 2.7.3</p>
  <h3>Example</h3>
  <pre><code>PostNotification.objects.bulk_create(
     [PostNotification(related_user=user, post=instance) for user in users]
  )
  </code></pre>
  <p>throws the above exception</p>
  <h1>What I have tried and though was a success originally:</h1>
  <p>I though that simply running:
  <code>BaseClass.objects.bulk_create(list_of_SubClass_objects)</code> instead of <code>SubClass.objects.bulk_create(list_of_SubClass_objects)</code> would work and return a list of SubClass values, but subsequently running <code>SubClass.objects.all()</code> would return an empty result. The bulk_create() would only create a Notification base class object for each item in the list.</p>