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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 load_config(cls):
 """ Load global and local configuration files and update if needed."""

        config_file = os.path.expanduser(cls.home_config)
        global_conf = cls.load(config_file, 'global')
        cls.load(cls.local_config, 'local')
        # update global configuration if needed
        cls.update_config(config_file, global_conf)