paddlepaddle2.2.2无法使用import paddle.fluid as fluid

抱歉，我之前的回答有些问题。确实，PaddlePaddle 2.2.2已经不再使用`fluid`模块，而是使用`paddle`模块。下面是修改后的代码：

import paddle
import numpy as np

def ccm():
    """Generates random RGB -> Camera color correction matrices."""
    # Fixed XYZ -> Camera CCM.
    cam2xyz = [[0.4679,0.2145,0.3176],[0.1433,0.8236,0.0331],[0.0003,-0.3607,1.3604]]
    xyz2cam = paddle.to_tensor(np.linalg.inv(np.array(cam2xyz)).astype(np.float32))

    # Multiplies with RGB -> XYZ to get RGB -> Camera CCM.
    rgb2xyz = paddle.to_tensor([[0.4124564, 0.3575761, 0.1804375], [0.2126729, 0.7151522, 0.0721750], [0.0193339, 0.1191920, 0.9503041]])
    rgb2cam = paddle.matmul(xyz2cam, rgb2xyz)

    # Normalizes each row.
    rgb2cam = rgb2cam / paddle.reduce_sum(rgb2cam, axis=-1, keepdim=True)
    return rgb2cam

def gains():
    """Generates random gains for brightening and white balance."""
    # RGB gain represents brightening.
    rgb_gain = 1.0

    # Red and blue gains represent white balance.
    red_gain = 1.0 / 0.5527
    blue_gain = 1.0 / 0.4844
    return rgb_gain, red_gain, blue_gain