@utilities.arguments_not_none<EOL><INDENT>def get_grade_entries(self, assessment_taken_id):<DEDENT>
<EOL>raise errors.IllegalState()<EOL>
Gets a list of grade entries for this assessment.

        Each grade entry may indicate a grade or score input by multiple
        graders.

        arg:    assessment_taken_id (osid.id.Id): ``Id`` of the
                ``AssessmentTaken``
        return: (osid.grading.GradeEntryList) - a list of grade entries
        raise:  IllegalState - ``are_results_available()`` is ``false``
        raise:  NotFound - ``assessment_taken_id`` is not found
        raise:  NullArgument - ``assessment_taken_id`` is ``null``
        raise:  OperationFailed - unable to complete request
        raise:  PermissionDenied - authorization failure
        *compliance: mandatory -- This method must be implemented.*