title: Django duplicate model definition/fields
body: <p>Here's what I was using:</p>
  
  <pre><code>class a(models.Model):
      x = models.CharField()
  
  class b(a):
      pass
  </code></pre>
  
  <p>The problem with this is that when an instance of b is created, an instance of a is also created, I'm guessing this is because b is inheriting some property that Django assigns such as the database table. I would like to have b have all the fields and methods so that this duplication does not happen. How can this be done <strong>without simply copy and pasting all the code from a to b or using an abstract base class c and have a and b both inherit from c (I'd like to only have two models/classes)?</strong> Would you have to use metaclasses?</p>