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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 set(self, key, value, confidence=100):
 """ Defines the given value with the given confidence, unless the same value is already defined with a higher confidence level. """

        if value is None:
            return
        if key in self.info:
            old_confidence, old_value = self.info.get(key)
            if old_confidence >= confidence:
                return
        self.info[key] = (confidence, value)