BlindWaterMar报错No module named cv2

python2的版本：Python 2.7.18
在用BlindWaterMark去除盲水印的时候（https://github.com/chishaxie/BlindWaterMark）报错：

Traceback (most recent call last):
  File "bwm.py", line 49, in 
    import cv2
ImportError: No module named cv2

去安装cv2模块
报错

...
Installing build dependencies ... done
Getting requirements to build wheel ... error
 ERROR: Command errored out with exit status 1:
...

解决办法【https://blog.csdn.net/qq_30000801/article/details/112349706】

python2 -m pip install opencv-python==4.2.0.32

没有python2命令？
如果同时安装了python2和3，可以修改一下exe文件名做一个区分，或者直接运行python2文件夹下的python命令安装opencv