Unable to open camera (OpenCV)

https://github.com/JetsonHacksNano/CSI-Camera

When I try to call if cap.isOpened(): in python3, I get false in return. However, when I use python2.7 and run the same script the camera loads just fine. Is sudo apt install python3-opencv the wrong package to use for the JetsonNano and python3?

This sounds like some library is missing in python3 opencv. Python3 also uses other 3rd party library to read the usb camera.