title: Display the str or unicode of an objet on deletion of one of its ManyToManyField
body: <p>I have declared in Django admin.py an <code>oeuvre</code> class with a <code>types</code> ManyToManyField to an <code>TypeOeuvre</code> class.</p>
  
  <pre><code>class Oeuvre(models.Model):
      titre = models.CharField(max_length=510)
      types = models.ManyToManyField('TypeOeuvre',
                                     blank=True,
                                     verbose_name="Type(s) de l'œuvre")
      class Meta:
          ordering = ['titre']
  
      def __unicode__(self):
          return "{0} [{1}]".format(self.titre[:200], self.id)
  
  class TypeOeuvre(models.Model):
      intitule = models.CharField(max_length=100, verbose_name='Intitulé')
      commentaire = models.CharField(max_length=255,
                                     verbose_name='Commentaire',
                                     blank=True)
  
      class Meta:
          ordering = ['intitule']
          verbose_name = "Type d'œuvre"
          verbose_name_plural = "Types d'œuvres"
  
      def __unicode__(self):
          return self.intitule
  </code></pre>
  
  <p>However, when I try to delete a TypeOeuvre object in Django Admin for which relations to one <em>oeuvre</em> exists, the "Are you sure?" warnings do not explicitly mention the name of the <em>oeuvre</em>:</p>
  
  <p>Oeuvre-typeoeuvre relationship: Oeuvre_types object</p>
  
  <p><a href="https://i.stack.imgur.com/3gT0J.png" rel="nofollow"><img src="https://i.stack.imgur.com/3gT0J.png" alt="Are you sure"></a></p>
  
  <p>Is there a way to display the name of the oeuvres linked to the type ?</p>
  
  <p>Thanks,</p>