No module named CV2

python2 Version of ：Python 2.7.18
In use BlindWaterMark When removing blind watermark （https://github.com/chishaxie/BlindWaterMark） Report errors ：

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

To install cv2 modular
Report errors

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

terms of settlement 【https://blog.csdn.net/qq_30000801/article/details/112349706】

python2 -m pip install opencv-python==4.2.0.32

No, python2 command ？
If it's installed at the same time python2 and 3, It can be modified exe Make a distinction between file names , Or run it directly python2 Under folder python Command to install opencv