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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 deriv(self, p):
 """ Derivative of CDF link Parameters p : array-like mean parameters Returns ------- g'(p) : array The derivative of CDF transform at `p` Notes ----- g'(`p`) = 1./ `dbn`.pdf(`dbn`.ppf(`p`)) """

        p = self._clean(p)
        return 1. / self.dbn.pdf(self.dbn.ppf(p))