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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 mu(self, lp, dist):
 """ glm mean function, ie inverse of link function this is useful for going from the linear prediction to mu Parameters lp : array-like of legth n dist : Distribution instance Returns ------- mu : np.array of length n """

        elp = np.exp(lp)
        return dist.levels * elp / (elp + 1)