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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 override_level_names(self, mapping):
 """Rename level names. :param mapping: Mapping level names to new ones :type mapping: dict """

        if not isinstance(mapping, dict):
            return
        for key, val in mapping.items():
            if key in self._level_names:
                self._level_names[key] = val