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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 setting(self, setting_name, default=None):
 # type: (str) -> Any """ Retrieve a setting value. """

        keys = setting_name.split(".")

        config = self._content
        for key in keys:
            if key not in config:
                return default

            config = config[key]

        return config