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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 normalize(self):
 """Replace rectangle with its finite version."""

        if self.x1 < self.x0:
            self.x0, self.x1 = self.x1, self.x0
        if self.y1 < self.y0:
            self.y0, self.y1 = self.y1, self.y0
        return self