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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 _compute_delta_beta(self, df, events, start, stop, weights):
 """ approximate change in betas as a result of excluding ith row"""


        score_residuals = self._compute_residuals(df, events, start, stop, weights) * weights[:, None]

        naive_var = inv(self._hessian_)
        delta_betas = -score_residuals.dot(naive_var) / self._norm_std.values

        return delta_betas