Fix PEP8 compliance...

netbox/dcim/fields.py

@@ -5,10 +5,10 @@ from django.db import models
 
 from .formfields import MACAddressFormField
 
+
 class mac_unix_expanded_uppercase(mac_unix_expanded):
     word_fmt = '%.2X'
 
-
 class MACAddressField(models.Field):
     description = "PostgreSQL MAC Address field"