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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 widen(self, other):
 """ Widen current range. """

        if self.low < other.low:
            low = -float("inf")
        else:
            low = self.low
        if self.high > other.high:
            high = float("inf")
        else:
            high = self.high
        return Interval(low, high)