import cv2
File “/usr/local/lib/python3.6/dist-packages/cv2/init.py”, line 3, in
from .cv2 import *
ImportError: libXext.so.6: cannot open shared object file: No such file or directory
解决：
ubuntu：apt update；apt-get install libsm-dev libxrender1 libxext6
centos：yum install libXext libSM libXrender
