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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 _g(self, x, tau):
 """ analytic solution of integral for NFW profile to compute deflection angel and gamma :param x: R/Rs :type x: float >0 """

        return tau ** 2 * (tau ** 2 + 1) ** -2 * (
                (tau ** 2 + 1 + 2 * (x ** 2 - 1)) * self.F(x) + tau * np.pi + (tau ** 2 - 1) * np.log(tau) +
                np.sqrt(tau ** 2 + x ** 2) * (-np.pi + self.L(x, tau) * (tau ** 2 - 1) * tau ** -1))