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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 know(self, what, confidence):
 """Know something with the given confidence, and return self for chaining. If confidence is higher than that of what we already know, replace what we already know with what you're telling us. """

        if confidence > self.confidence:
            self.best = what
            self.confidence = confidence
        return self