it's arguably better practice to limit the exceptions you're catching with a `try/except` block, like so:

```python
try:
    c = (CollectionAddon.objects.using('default')
         .get(collection=self.id, addon=addon))
except CollectionAddon.DoesNotExist:
    pass
else:
    c.comments = comment
    c.save(force_update=True)
```