import cv2 as cv2
import numpy as np

print(f'cv2 v.{cv.__version__}')

x = np.uint8([250])
y = np.uint8([10])
 
print( cv.add(x,y) ) # 250+10 = 260 => 255
# [[255]]
 
print( x+y )          # 250+10 = 260 % 256 = 4
# [4]