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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:
 def remove_subscriber(self, message):
 """ Remove a subscriber based on token. :param message: the message """

        logger.debug("Remove Subcriber")
        host, port = message.destination
        key_token = hash(str(host) + str(port) + str(message.token))
        try:
            self._relations[key_token].transaction.completed = True
            del self._relations[key_token]
        except KeyError:
            logger.warning("No Subscriber")