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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 __on_publish(self, client, userdata, mid):
 # pylint: disable=W0613 """ A message has been published by a server :param client: Client that received the message :param userdata: User data (unused) :param mid: Message ID """

        try:
            self.__in_flight[mid].set()
        except KeyError:
            pass