docs: def get_gradebook_columns_by_gradebook(self, gradebook_id):
          """Gets the list of gradebook columns associated with a ``Gradebook``.
  
          arg:    gradebook_id (osid.id.Id): ``Id`` of the ``Gradebook``
          return: (osid.grading.GradebookColumnList) - list of related
                  gradebook columns
          raise:  NotFound - ``gradebook_id`` is not found
          raise:  NullArgument - ``gradebook_id`` is ``null``
          raise:  OperationFailed - unable to complete request
          raise:  PermissionDenied - authorization failure
          *compliance: mandatory -- This method must be implemented.*
  
          """
          # Implemented from template for
          # osid.resource.ResourceBinSession.get_resources_by_bin
          mgr = self._get_provider_manager('GRADING', local=True)
          lookup_session = mgr.get_gradebook_column_lookup_session_for_gradebook(gradebook_id, proxy=self._proxy)
          lookup_session.use_isolated_gradebook_view()
          return lookup_session.get_gradebook_columns()