Exception on image delete

[olfway]

Issue type: bug report

Python version: 2.7.13
NetBox version: v2.0-beta3-1-gb8b912b

I'm trying to delete image attached to site:
http://netbox.mtxc.co/extras/image-attachments/1/delete/

got exception:

Internal Server Error: /extras/image-attachments/1/delete/
Traceback (most recent call last):
  File "/usr/local/lib/python2.7/site-packages/django/core/handlers/exception.py", line 41, in inner
    response = get_response(request)
  File "/usr/local/lib/python2.7/site-packages/django/core/handlers/base.py", line 187, in _get_response
    response = self.process_exception_by_middleware(e, request)
  File "/usr/local/lib/python2.7/site-packages/django/core/handlers/base.py", line 185, in _get_response
    response = wrapped_callback(request, *callback_args, **callback_kwargs)
  File "/usr/local/lib/python2.7/site-packages/django/views/generic/base.py", line 68, in view
    return self.dispatch(request, *args, **kwargs)
  File "/usr/local/lib/python2.7/site-packages/django/contrib/auth/mixins.py", line 92, in dispatch
    return super(PermissionRequiredMixin, self).dispatch(request, *args, **kwargs)
  File "/usr/local/lib/python2.7/site-packages/django/views/generic/base.py", line 88, in dispatch
    return handler(request, *args, **kwargs)
  File "/opt/netbox/utilities/views.py", line 261, in get
    'return_url': self.get_return_url(request, obj),
  File "/opt/netbox/extras/views.py", line 30, in get_return_url
    return imageattachment.obj.get_absolute_url()
AttributeError: 'ImageAttachment' object has no attribute 'obj'