title: How can I remove the add and change buttons from a TabularInline admin field?
body: <p>I have models <code>A</code>, <code>B</code>, and <code>AB</code>.
  <code>A</code> objects have a <code>ManyToManyField</code> called <code>A.m</code> that can link to many <code>B</code> objects, through my intermediary model <code>AB</code>.<br>
  I have a very nice <code>TabularInline</code> section full of <code>AB</code> objects, on my admin page for my <code>A</code> model.</p>
  
  <p>All is well.  Except that the <code>TabularInline</code> section shows "Add" and "Change" buttons for the <code>B</code> object in each <code>AB</code> object's row, and I want to remove those buttons.  I still want to be able to add, change, and delete <code>AB</code> objects rows, just not the <code>B</code> objects they reference.</p>
  
  <p>I have tried setting the <code>can_add_related</code>, <code>can_change_related</code>, <code>can_delete_related</code> attributes to <code>False</code>, but this does nothing.</p>
  
  <pre><code>class ABInline(admin.TabularInline):
      model = AB
      def get_form(self, request, obj=None, **kwargs):
          form = super(ABInline, self).get_form(request, obj, **kwargs)
          form.base_fields['m'].widget.can_add_related = False
          form.base_fields['m'].widget.can_change_related = False
          form.base_fields['m'].widget.can_delete_related = False
          return form
  </code></pre>
  
  <p>Is this a bug?  Or is there a different way to accomplish this for <code>TabularInline</code> fields?</p>