Code refactoring and bug fixes

powerdnsadmin/models/domain_setting.py

@@ -1,3 +1,5 @@
+import traceback
+
 from flask import current_app
 
 from .base import db
@@ -32,4 +34,4 @@ class DomainSetting(db.Model):
                 'Unable to set DomainSetting value. DETAIL: {0}'.format(e))
             current_app.logger.debug(traceback.format_exc())
             db.session.rollback()
-            return False
+            return False