Changelog and misc cleanup

netbox/dcim/models.py

@@ -10,7 +10,7 @@ from django.contrib.postgres.fields import ArrayField, JSONField
 from django.core.exceptions import ObjectDoesNotExist, ValidationError
 from django.core.validators import MaxValueValidator, MinValueValidator
 from django.db import models
-from django.db.models import Count, Q, ObjectDoesNotExist
+from django.db.models import Count, Q
 from django.urls import reverse
 from django.utils.encoding import python_2_unicode_compatible
 from mptt.models import MPTTModel, TreeForeignKey