@abc.abstractmethod<EOL><INDENT>def get_gradebook_column_summary(self, gradebook_column_id):<DEDENT>
return<EOL>
Gets the ``GradebookColumnSummary`` for summary results.

        :param gradebook_column_id: ``Id`` of the ``GradebookColumn``
        :type gradebook_column_id: ``osid.id.Id``
        :return: the gradebook column summary
        :rtype: ``osid.grading.GradebookColumnSummary``
        :raise: ``NotFound`` -- ``gradebook_column_id`` is not found
        :raise: ``NullArgument`` -- ``gradebook_column_id`` is ``null``
        :raise: ``OperationFailed`` -- unable to complete request
        :raise: ``PermissionDenied`` -- authorization failure
        :raise: ``Unimplemented`` -- ``has_summary()`` is ``false``

        *compliance: mandatory -- This method is must be implemented.*