Move IPAddressManager to a separate file

netbox/ipam/managers.py

@@ -0,0 +1,16 @@
+from django.db import models
+from django.db.models.expressions import RawSQL
+
+
+class IPAddressManager(models.Manager):
+
+    def get_queryset(self):
+        """
+        By default, PostgreSQL will order INETs with shorter (larger) prefix lengths ahead of those with longer
+        (smaller) masks. This makes no sense when ordering IPs, which should be ordered solely by family and host
+        address. We can use HOST() to extract just the host portion of the address (ignoring its mask), but we must
+        then re-cast this value to INET() so that records will be ordered properly. We are essentially re-casting each
+        IP address as a /32 or /128.
+        """
+        qs = super().get_queryset()
+        return qs.annotate(host=RawSQL('INET(HOST(ipam_ipaddress.address))', [])).order_by('family', 'host')