diff -up pyparted-3.9/src/pydisk.c.orig pyparted-3.9/src/pydisk.c

--- pyparted-3.9/src/pydisk.c.orig	2018-01-12 13:47:27.488464829 -0500

+++ pyparted-3.9/src/pydisk.c	2018-01-12 13:47:04.129550934 -0500

@@ -209,7 +209,11 @@ int _ped_Partition_init(_ped_Partition *

                 PyErr_SetString(PartitionException, partedExnMessage);

             }

         } else {

-            PyErr_Format(PartitionException, "Could not create new partition on device %s", disk->dev->path);

+            if (disk == NULL) {

+               PyErr_Format(PartitionException, "Could not create new partition");

+            } else {

+                PyErr_Format(PartitionException, "Could not create new partition on device %s", disk->dev->path);

+            }

         }

         self->disk = self->fs_type = NULL;