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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 mid_pt(self):
 """Midpoint of this interval product."""

        midp = (self.max_pt + self.min_pt) / 2.
        midp[~self.nondegen_byaxis] = self.min_pt[~self.nondegen_byaxis]
        return midp