def img_random_brightness(img):
    return tf.image.random_brightness(img, .2)

test_random_brightness = (train_data.map(lambda img, label: img_random_brightness(img)))
plt.figure(figsize=(6,6))
for img in test_random_brightness.take(1):
    for num in range(16):
        ax = plt.subplot(4,4,num+1)
        plt.imshow((img[num].numpy()).astype("uint8"))
        plt.axis("off")  
plt.suptitle("Random Brightness")
plt.tight_layout()
plt.show()

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