title: How to replace content_type and object_id fields by a field with actual object in admin inline?
body: <p>I have inline, which shows data of <code>contenttype</code> model, so instead of real objects, I see <code>content_type</code> and <code>object_id</code> fields. I can <code>exclude</code> these fields - this is not a problem, but also I want to get real object as <code>selected</code> with another <code>Places</code> in a dropdown list. Could anyone tell me, how can I do this?</p>
  
  <p>Model:</p>
  
  <pre><code>class Criterias(models.Model):
      name = ...
  
  class Places(models.Model):
      name = ...
  
  class PlacesToCriterias(models.Model):
      content_type = models.ForeignKey(ContentType, on_delete=models.CASCADE)
      object_id = models.PositiveIntegerField()
      content_object = GenericForeignKey()
  
      criteria_group = models.ForeignKey(Criterias)
  </code></pre>
  
  <p>Admin:</p>
  
  <pre><code>class CriteriaPlacesInlineAdmin(admin.TabularInline):
      model = PlacesToCriterias
  
  class CriteriasAdmin(admin.ModelAdmin):
      inlines = [CriteriaPlacesInlineAdmin]
  
  admin.site.register(Criterias, CriteriasAdmin)
  </code></pre>
  
  <p>I can add to <code>CriteriaPlacesInlineAdmin</code> a <code>form</code>, something like:</p>
  
  <pre><code>class CriteriaPlacesChoicesFieldForm(forms.ModelForm):
      places = forms.ModelChoiceField(PlaceTypesGroups.objects.all(), label='place')
  </code></pre>
  
  <p>but how can I pass\add <code>object_id</code> to this form\query in order to get 'selected' place in the dropdown list?</p>