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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 clientConnected(self, proto):
 """ Called when a client connects to the bus. This method assigns the new connection a unique bus name. """

        proto.uniqueName = ':1.%d' % (self.next_id,)
        self.next_id += 1
        self.clients[proto.uniqueName] = proto