How to return Objects in a Many to Many Django

Question

Consider the model

class Dealership(models.Model):
    dealership = models.CharField(max_length=50)

class Ordered(models.Model):
    customer = models.ForeignKey("Customer")
    dealership = models.ManyToManyField("Dealership")
    status = models.CharField(max_length=2, choices=status_list, default='p')

I tried to

$ ./manage.py shell
>>> from new_way.core.models import Ordered, Dealership
>>> q = Ordered.objects.all()[:5]
>>> [i.dealership for i in q.dealership.all]

Generated the following error:

Traceback (most recent call last):
  File "<console>", line 1, in <module>
AttributeError: 'QuerySet' object has no attribute 'dealership'

How to Return

Ordered.dealership.dealership

all Dealership by Ordered.

Answer 1

The mistake says 'QuerySet' object has no attribute 'dealership'. You’re actually doing this:

ordens = Ordered.objects.all().dealership.all()

For the code to work properly you must loop the orders and then make a second loop.

lista = []
ordens = Ordered.objects.all()
for ordem in ordens:
    for o in ordem.dealership.all():
        lista.append(o.dealership)

or

lista = [o.dealership for o in ordem.dealership.all() for ordem in Ordered.objects.all()]