Fix remove_null_from_text_fields migration

apps/map/migrations/0069_remove_null_from_text_fields.py

@@ -5,8 +5,6 @@ from __future__ import unicode_literals
 from django.db import migrations, models
 import multiselectfield.db.fields
 
-from apps.map.models import CaseStudy
-
 string_fields = [
     'additional_technical_details',
     'associated_infrastructure',
@@ -58,13 +56,17 @@ string_fields = [
 def remove_nulls(apps, schema_editor):
     # We can't import the Person model directly as it may be a newer
     # version than this migration expects. We use the historical version.
-    study = apps.get_model('map', 'CaseStudy')
+    CaseStudy = apps.get_model('map', 'CaseStudy')
     for study in CaseStudy.objects.all():
         for field in string_fields:
             if getattr(study, field) == None:
                 setattr(study, field, '')
 
-        study.save()
+        try:
+            study.save()
+        except:
+            from pdb import set_trace; set_trace()
+
 
 
 class Migration(migrations.Migration):
@@ -74,5 +76,5 @@ class Migration(migrations.Migration):
     ]
 
     operations = [
-        migrations.RunPython(remove_nulls),
+        migrations.RunPython(remove_nulls, migrations.RunPython.noop),
     ]