'Second derivative of the Cauchy link function.
Parameters
p: array-like
Probabilities
Returns
g\'\'(p) : array
Value of the second derivative of Cauchy link function at `p`'

def deriv2(self, p):

    a = (np.pi * (p - 0.5))
    d2 = (((2 * (np.pi ** 2)) * np.sin(a)) / (np.cos(a) ** 3))
    return d2
