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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_smooth_during_construction(self, xi):
 """ Evaluate value of smooth at x-value xi. Parameters xi : float Value of x where smooth value is desired Returns ------- smooth_here : float Value of smooth s(xi) """

        if self._variance_in_window:
            beta = self._covariance_in_window / self._variance_in_window
            alpha = self._mean_y_in_window - beta * self._mean_x_in_window
            value_of_smooth_here = beta * (xi) + alpha
        else:
            value_of_smooth_here = 0.0
        return value_of_smooth_here