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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 _build_information(self):
 """Build the inverse of hessian of the log likelihood at theta_ """

        lag_time = float(self.lag_time)

        # only the "active set" of variables not at the bounds of the
        # feasible set.
        inds = np.where(self.theta_ != 0)[0]

        hessian = _ratematrix.hessian(
            self.theta_, self.countsmat_, t=lag_time, inds=inds)

        self.information_ = np.zeros((len(self.theta_), len(self.theta_)))
        self.information_[np.ix_(inds, inds)] = scipy.linalg.pinv(-hessian)