def get_filediff(self, request, *args, **kwargs):
        """Returns the FileDiff, or an error, for the given parameters."""
        draft_resource = resources.review_request_draft

        try:
            draft = draft_resource.get_object(request, *args, **kwargs)
        except ObjectDoesNotExist:
            return DOES_NOT_EXIST

        if not draft_resource.has_access_permissions(request, draft):
            return self.get_no_access_error(request)

        try:
            return resources.draft_filediff.get_object(request, *args,
                                                       **kwargs)
        except __HOLE__:
            return DOES_NOT_EXIST
dataset/ETHPy150Open reviewboard/reviewboard/reviewboard/webapi/resources/draft_original_file.py/DraftOriginalFileResource.get_filediff