Got "ERROR cinder.volume.drivers.netapp.dataontap.nfs_cmode AttributeError: type object 'exceptions.Exception' has no attribute 'NotFound'"

Issue

• Please check whether there is any problem with the error on controller node below.
• What is the problem or behavior that is a problem?

• What kind of behavior is expected?

  2016-12-23 10:32:13.560 24342 ERROR cinder.volume.drivers.netapp.dataontap.nfs_cmode [req-17278013-7174-4425-aec6-0bfe740dd717 - - - - -] Copy offload workflow unsuccessful. type object 'exceptions.Exception' has no attribute 'NotFound'
  2016-12-23 10:32:13.560 24342 ERROR cinder.volume.drivers.netapp.dataontap.nfs_cmode Traceback (most recent call last):
  2016-12-23 10:32:13.560 24342 ERROR cinder.volume.drivers.netapp.dataontap.nfs_cmode   File "/usr/lib/python2.7/site-packages/cinder/volume/drivers/netapp/dataontap/nfs_cmode.py", line 425, in copy_image_to_volume
  2016-12-23 10:32:13.560 24342 ERROR cinder.volume.drivers.netapp.dataontap.nfs_cmode     image_id)
  2016-12-23 10:32:13.560 24342 ERROR cinder.volume.drivers.netapp.dataontap.nfs_cmode   File "/usr/lib/python2.7/site-packages/cinder/utils.py", line 872, in trace_method_logging_wrapper
  2016-12-23 10:32:13.560 24342 ERROR cinder.volume.drivers.netapp.dataontap.nfs_cmode     return f(*args, **kwargs)
  2016-12-23 10:32:13.560 24342 ERROR cinder.volume.drivers.netapp.dataontap.nfs_cmode   File "/usr/lib/python2.7/site-packages/cinder/utils.py", line 872, in trace_method_logging_wrapper
  2016-12-23 10:32:13.560 24342 ERROR cinder.volume.drivers.netapp.dataontap.nfs_cmode     return f(*args, **kwargs)
  2016-12-23 10:32:13.560 24342 ERROR cinder.volume.drivers.netapp.dataontap.nfs_cmode   File "/usr/lib/python2.7/site-packages/cinder/volume/drivers/netapp/dataontap/nfs_cmode.py", line 512, in _copy_from_img_service
  2016-12-23 10:32:13.560 24342 ERROR cinder.volume.drivers.netapp.dataontap.nfs_cmode     except Exception.NotFound:
  2016-12-23 10:32:13.560 24342 ERROR cinder.volume.drivers.netapp.dataontap.nfs_cmode AttributeError: type object 'exceptions.Exception' has no attribute 'NotFound'
  2016-12-23 10:32:13.560 24342 ERROR cinder.volume.drivers.netapp.dataontap.nfs_cmode