title: ForeignKey field related to abstract model in Django
body: <p>I have this model:</p>
  
  <pre><code>class BaseModel(models.Model):
      ....
  
      class Meta:
          abstract = True
  
  
  class ModelA(BaseModel):
      ....
  
  class ModelB(BaseModel):
      ....
  
  
  class MyExtModel(models.Model)
      myfield = models.ForeignKey(BaseModel)
  </code></pre>
  
  <p>But this is not correct because I have <code>BaseModel</code> like <code>Abstract</code>. Infact I have an error when I try <code>makemigration</code> command.</p>
  
  <p>The error is:</p>
  
  <pre><code>ERRORS:
  myapp.MyExtModel.myfield: (fields.E300) Field defines a relation with model 'BaseModel', which is either not installed, or is abstract.
  </code></pre>
  
  <p>Is there a way to use an abstract base model?</p>
  
  <p>I also tried to use:</p>
  
  <pre><code>myfield = models.ForeignKey(BaseModel, related_name="%(app_label)s_%(class)s_related")
  </code></pre>