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"""
Many-to-many relationships
To define a many-to-many relationship, use ``ManyToManyField()``.
In this example, an ``Article`` can be published in multiple ``Publication``
objects, and a ``Publication`` has multiple ``Article`` objects.
"""
from __future__ import unicode_literals
from django.db import models
from django.utils.encoding import python_2_unicode_compatible
@python_2_unicode_compatible
class Publication(models.Model):
title = models.CharField(max_length=30)
def __str__(self):
return self.title
class Meta:
ordering = ('title',)
@python_2_unicode_compatible
class Article(models.Model):
headline = models.CharField(max_length=100)
# Assign a unicode string as name to make sure the intermediary model is
# correctly created. Refs #20207
publications = models.ManyToManyField(Publication, name='publications')
def __str__(self):
return self.headline
class Meta:
ordering = ('headline',)
# Models to test correct related_name inheritance
class AbstractArticle(models.Model):
class Meta:
abstract = True
ordering = ('title',)
publications = models.ManyToManyField(Publication, name='publications', related_name='+')
class InheritedArticleA(AbstractArticle):
pass
class InheritedArticleB(AbstractArticle):
pass
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