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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 apply_config(self, config):
 """ Sets the `discovery` and `meta_cluster` attributes, as well as the configured + available balancer attributes from a given validated config. """

        self.discovery = config["discovery"]
        self.meta_cluster = config.get("meta_cluster")
        for balancer_name in Balancer.get_installed_classes().keys():
            if balancer_name in config:
                setattr(self, balancer_name, config[balancer_name])