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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 async def update_websub(self, config, hub):
 """ Update WebSub hub to know about this feed """

        try:
            LOGGER.debug("WebSub: Notifying %s of %s", hub, self.url)
            request = await utils.retry_post(
                config,
                hub,
                data={
                    'hub.mode': 'publish',
                    'hub.url': self.url
                })

            if request.success:
                LOGGER.info("%s: WebSub notification sent to %s",
                            self.url, hub)
            else:
                LOGGER.warning("%s: Hub %s returned status code %s: %s", self.url, hub,
                               request.status, request.text)
        except Exception as err:  # pylint:disable=broad-except
            LOGGER.warning("WebSub %s: got %s: %s",
                           hub, err.__class__.__name__, err)