def METHOD_NAME(self, instance_id):
    """
    Retrieves the given person.
    """
    relations = self.get_bool_parameter("relations")
    try:
        instance = self.get_model_or_404(instance_id)
        result = self.serialize_instance(instance, relations=relations)
        self.check_read_permissions(result)
        result = self.clean_get_result(result)
    except StatementError as exception:
        current_app.logger.error(str(exception), exc_info=1)
        return {"message": str(exception)}, 400
    except ValueError:
        abort(404)
    return result, 200