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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 add_value(self, val:float)->None:
        "Add `val` to calculate updated smoothed value."
        self.n += 1
        self.mov_avg = self.beta * self.mov_avg + (1 - self.beta) * val
        self.smooth = self.mov_avg / (1 - self.beta ** self.n)