title: Can Django automatically create a related one-to-one model?
body: <p>I have two models in different apps: <code>ModelA</code> and <code>ModelB</code>.  They have a one-to-one relationship.  Is there a way django can automatically create and save <code>ModelB</code> when <code>ModelA</code> is saved?</p>
  <pre><code>class ModelA(models.Model):
      name = models.CharField(max_length=30)
  
  class ModelB(models.Model):
      thing = models.OneToOneField(ModelA, primary_key=True)
      num_widgets = IntegerField(default=0)
  </code></pre>
  <p>When I save a new <code>ModelA</code> I want a entry for it to be saved automatically in <code>ModelB</code>.  How can I do this?  Is there a way to specify that in <code>ModelA</code>?  Or is this not possible, and I would just need to create and save <code>ModelB</code> in the view?</p>
  <p>Edited to say the models are in different apps.</p>