"""9. Many-to-many relationships via an intermediary tableFor many-to-many relationships that need extra fields on the intermediarytable, use an intermediary model.In this example, an ``Article`` can have multiple ``Reporter`` objects, andeach ``Article``-``Reporter`` combination (a ``Writer``) has a ``position``field, which specifies the ``Reporter``'s position for the given article(e.g. "Staff writer")."""from django.db import modelsclass Reporter(models.Model): first_name = models.CharField(max_length=30) last_name = models.CharField(max_length=30) def __unicode__(self): return u"%s %s" % (self.first_name, self.last_name)class Article(models.Model): headline = models.CharField(max_length=100) pub_date = models.DateField() def __unicode__(self): return self.headlineclass Writer(models.Model): reporter = models.ForeignKey(Reporter) article = models.ForeignKey(Article) position = models.CharField(max_length=100) def __unicode__(self): return u'%s (%s)' % (self.reporter, self.position)