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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 level_name(self, level=None):
 """Return the name of the given level value. If level is None, return the name of the current level. Parameters level : logging level constant The logging level constant whose name to retrieve. Returns ------- level_name : str The name of the logging level. """

        if level is None:
            level = self._log_level
        return self.LEVELS[level]