Comment 1 for bug 1522128

Same Traceback issue occurs on a 14.04.3 enabled machine while testing, though this system's /dev/sdc device doesn't seem to have any "unknown" in its data:

Name: /dev/sda
 Description: ATA Disk
 Vendor: Seagate
 Product: ST2000DM001-1ER1
 Size: 2000GB
Name: /dev/sdb
 Description: ATA Disk
 Vendor: Seagate
 Product: ST2000DM001-1ER1
 Size: 2000GB
Name: /dev/sdc
 Description: SCSI Disk
 Vendor: Generic-
 Product: USB3.0 CRW
Traceback (most recent call last):
  File "/tmp/nest-qijsnwl9.90740e0964b0bdb3458bc6f50f16558b9c8e5cb7dee2a7756bd5cac781ed1136/disk_info", line 72, in <module>
    sys.exit(main())
  File "/tmp/nest-qijsnwl9.90740e0964b0bdb3458bc6f50f16558b9c8e5cb7dee2a7756bd5cac781ed1136/disk_info", line 64, in main
    int(disk.find('size').text) / (1000**3)))
AttributeError: 'NoneType' object has no attribute 'text'