Improve formatting after previous commit

lib/ansible/modules/cloud/amazon/ec2.py

@@ -919,12 +919,13 @@ def create_instances(module, ec2, override_count=None):
                 # The instances returned through ec2.run_instances above can be in
                 # terminated state due to idempotency. See commit 7f11c3d for a complete
                 # explanation.
-                terminated_instances = [ str(instance.id) for instance in res.instances
-                                        if instance.state == 'terminated' ]
+                terminated_instances = [
+                    str(instance.id) for instance in res.instances if instance.state == 'terminated'
+                ]
                 if terminated_instances:
                     module.fail_json(msg = "Instances with id(s) %s " % terminated_instances +
-                                        "were created previously but have since been terminated - " +
-                                        "use a (possibly different) 'instanceid' parameter")
+                                           "were created previously but have since been terminated - " +
+                                           "use a (possibly different) 'instanceid' parameter")
 
             else:
                 if private_ip: