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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 _ray_step(self, x, y, alpha_x, alpha_y, delta_T):
 """ ray propagation with small angle approximation :param x: co-moving x-position :param y: co-moving y-position :param alpha_x: deflection angle in x-direction at (x, y) :param alpha_y: deflection angle in y-direction at (x, y) :param delta_T: transversal angular diameter distance to the next step :return: """

        x_ = x + alpha_x * delta_T
        y_ = y + alpha_y * delta_T
        return x_, y_