def update_webhook(self, url, headers=None):
        """Register new webhook for incoming subscriptions.

        If a webhook is already set, this will do an overwrite.

        :param str url: the URL with listening webhook (Required)
        :param dict headers: K/V dict with additional headers to send with request
        :return: void
        """
        headers = headers or {}
        api = self._get_api(mds.NotificationsApi)

        # Delete notifications channel
        api.delete_long_poll_channel()

        # Send the request to register the webhook
        webhook_obj = WebhookData(url=url, headers=headers)
        api.register_webhook(webhook_obj)
        return