Fixes: #4396 - Fix typing on interface serializer

docs/release-notes/version-2.7.md

@@ -10,6 +10,7 @@
 
 ### Bug Fixes
 
+* [#4396](https://github.com/netbox-community/netbox/issues/4395) - Fix typing of count_ipaddresses on interface serializer
 * [#4418](https://github.com/netbox-community/netbox/issues/4418) - Fail cleanly when trying to import multiple device types simultaneously
 * [#4438](https://github.com/netbox-community/netbox/issues/4438) - Fix exception when disconnecting a cable from a power feed
 * [#4439](https://github.com/netbox-community/netbox/issues/4439) - Tweak display of unset custom integer fields

netbox/dcim/api/serializers.py

@@ -530,6 +530,7 @@ class InterfaceSerializer(TaggitSerializer, ConnectedEndpointSerializer):
     )
     cable = NestedCableSerializer(read_only=True)
     tags = TagListSerializerField(required=False)
+    count_ipaddresses = serializers.IntegerField(read_only=True)
 
     class Meta:
         model = Interface