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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 _penalize_client(self, client):
 """Place client in the penalty box. :param client: Client object """

        if client in self.active_clients:  # hasn't been removed yet
            log.warning("%r marked down.", client)
            self.active_clients.remove(client)
            self.penalty_box.add(client)
        else:
            log.info("%r not in active client list.")