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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 unpublish(self, daap_server):
 """ Unpublish a given server. If the server was not published, this method will not do anything. :param DAAPServer daap_server: DAAP Server instance to publish. """


        if daap_server not in self.daap_servers:
            return

        self.zeroconf.unregister_service(self.daap_servers[daap_server])

        del self.daap_servers[daap_server]