Using try inside for loop to retrieve object without exception

Question

I'm doing some form validation with Django for users adding a music album and its tracks to a database. Two albums of same name can exist as long as they're tied to diff. artists. This way, both artist name Beatles and Beatles Cover Band can both have an album called Hard Days Night in the db.

I've retrieved album objects with the same name called into a list called retrieve_albums and check each object for its artist using a for loop. The problem is that when I use .get on the queryset, I get error DoesNotExist: <object> matching query does not exist, which I say is a sort of descendant error of NameError. So I try putting inside a try block as shown.

>>> check_duplicate = False
>>> for album in retrieve_albums:
...     try:
...         if album.artists.get(name='Major Lazer'):
...             check_duplicate = True
...             break
...     except NameError:
...         pass

By the way, since these are ManyToManyKeys, I can't just call album.artists(name=artist).

Ideally, the logic I'd like to do without try and except is:

for album in retrieve_albums:
    if album.artists.get(name='Major Lazer'):
        check_duplicate = True
        break
    else:
        continue

Using get throws a DoesNotExist error even just evaluating the if statement - it doesn't even get to the block. I also tried using album.artists.get(name='Major Lazer', None) but get SyntaxError: non-keyword arg after keyword arg

What's the best way to do this?

EDIT:

models.py for ref.

class Artist(models.Model):
    name = models.CharField(max_length=100, null=False, blank=False)
    short_bio = models.CharField(max_length=2000, null=False, blank=False)
    added = models.DateTimeField(auto_now=True, auto_now_add=False)
    updated = models.DateTimeField(auto_now=False, auto_now_add=True)

class Album(models.Model):
    name = models.CharField(max_length=150, null=False, blank=False)
    artists = models.ManyToManyField(Artist)
    active = models.BooleanField(default=True)
    slug = models.SlugField(null=True, blank=True)
    added = models.DateTimeField(auto_now=True, auto_now_add=False)
    updated = models.DateTimeField(auto_now=False, auto_now_add=True)

class Track(models.Model):
    name = models.CharField(max_length=200, null=False, blank=False)
    albums = models.ManyToManyField(Album)
    track_no = models.PositiveSmallIntegerField(null=True, blank=True)

Answer 1

Instead of get() use filter() and exists():

if album.artists.filter(name='Major Lazer').exists():
    check_duplicate = True 
    break
else:
    continue

Answer 2

album.artists is a Django QuerySet object, not a Python dict. You need to catch the DoesNotExist exception instead. You can import it into your current namespace with:

from django.core.exceptions import ObjectDoesNotExist

See the QuerySet API reference.