def METHOD_NAME(self, sizes, aspect_ratios):
    anchors = []
    for size in sizes:
        area = size**2.0
        for aspect_ratio in aspect_ratios:
            w = math.sqrt(area / aspect_ratio)
            h = aspect_ratio * w
            x0, y0, x1, y1 = -w / 2.0, -h / 2.0, w / 2.0, h / 2.0
            anchors.append([x0, y0, x1, y1])
    return paddle.to_tensor(anchors, dtype='float32')