def enforce_notifications(self, data):
        """
        Add default notification for current owner if none exist.
        This ensures that the default notifications are added in the event of owner change.
        Old owner notifications are retained unless explicitly removed later in the code path.
        :param data:
        :return:
        """
        if data.get("owner"):
            notification_name = "DEFAULT_{}".format(
                data["owner"].split("@")[0].upper()
            )

            # Even if one default role exists, return
            # This allows a User to remove unwanted default notification for current owner
            if any(n.label.startswith(notification_name) for n in data["notifications"]):
                return data

            data[
                "notifications"
            ] += notification_service.create_default_expiration_notifications(
                notification_name, [data["owner"]]
            )

        return data

        Add default notification for current owner if none exist.
        This ensures that the default notifications are added in the event of owner change.
        Old owner notifications are retained unless explicitly removed later in the code path.
        :param data:
        :return:
        
lemur/certificates/schemas.py