FIX: Fix missing import

Presumably caused by Matt's IDE being overzealous again. I know I shouldn't be pushing to master but...one line fix...

assets/migrations/0008_auto_20191205_1937_squashed_0009_auto_20191205_2041.py

@@ -1,18 +1,19 @@
 # Generated by Django 2.0.13 on 2019-12-05 20:42
 
+import re
 from django.db import migrations, models
 import django.db.migrations.operations.special
 
 def forwards(apps, schema_editor):
     AssetModel = apps.get_model('assets', 'Asset')
-    
+
     for row in AssetModel.objects.all():
 
         row.asset_id = row.asset_id.upper()
         asset_search = re.search("^([A-Z0-9]*?[A-Z]?)([0-9]+)$", row.asset_id)
         if asset_search is None: # If the asset_id doesn't have a number at the end
             row.asset_id += "1"
-        
+
         asset_search = re.search("^([A-Z0-9]*?[A-Z]?)([0-9]+)$", row.asset_id)
         row.asset_id_prefix = asset_search.group(1)
         row.asset_id_number = int(asset_search.group(2))