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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_acq(self, x):
 """ Computes the Expected Improvement per unit of cost """

        m, s = self.model.predict(x)
        fmin = self.model.get_fmin()
        phi, Phi, u = get_quantiles(self.jitter, fmin, m, s)
        f_acqu = s * (u * Phi + phi)
        return f_acqu