title: How to create inline for a model with common referenced model in Django admin?
body: <p>So I have these kind of models:</p>
  
  <pre><code>def Profile(models.Model):
      user = OneToOneField(User, primary_key=True)
  
  def OtherProfile(models.Model):
      user = OneToOneField(User, primary_key=True)
  
  def Item(models.Model):
      user = ForeignKey(User)
  </code></pre>
  
  <p>And I want to have <code>ItemInline</code> in <code>ProfileAdmin</code> (and similarly in <code>OtherProfileAdmin</code>). I tried doing it like this:</p>
  
  <pre><code>class ItemInline(admin.TabularInLine):
      model = Item
  
  @admin.register(Profile)
  class ProfileAdmin(admin.ModelAdmin):
      inlines = [ItemInline]
  </code></pre>
  
  <p>However, this shows me this error:</p>
  
  <pre><code>&lt;class 'app.admin.ItemInline'&gt;: (admin.E202) 'api.Item' has no ForeignKey to 'api.Profile'.
  </code></pre>
  
  <p>How do I put the <code>ItemInline</code> into <code>ProfileAdmin</code>?</p>
  
  <p>I can't put <code>ForeignKey(Profile)</code> into the <code>Item</code>, because then I would not be able to access <code>Item</code> from <code>OtherProfile</code>.</p>