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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 dist(self, x1, x2):
 """Calculate the constant-weighted distance between two elements. Parameters x1, x2 : `ProductSpaceElement` Elements whose mutual distance is calculated. Returns ------- dist : float The distance between the elements. """

        dnorms = np.fromiter(
            ((x1i - x2i).norm() for x1i, x2i in zip(x1, x2)),
            dtype=np.float64, count=len(x1))

        if self.exponent == float('inf'):
            return self.const * np.linalg.norm(dnorms, ord=self.exponent)
        else:
            return (self.const ** (1 / self.exponent) *
                    np.linalg.norm(dnorms, ord=self.exponent))