Test in 77D

[maikovisky]

$ python tether.py 
super() takes at least 1 argument (0 given)
Exception TypeError: 'super() takes at least 1 argument (0 given)' in <bound method Camera.__del__ of <camera.camera.Camera object at 0x7f48d513b8d0>> ignored

[maikovisky]

$ python3 tether.py 
Error initializing camera.
GPhoto2 Error Code: -53

[rafasgj]

Please, provide versions for Python, Gphoto2 and libgphoto2. (Also, your 'distro' flavor and version might help.)

[maikovisky]

Ubuntu 18.04.2 LTS
Python3 3.6.8
Python 2.7.15+
GPhoto2 2.5.15-2
libgphoto2 2.5.16-2

[rafasgj]

The versions are similar to the ones being tested, only minor version differ.
The latest commits have improved error reporting.
Please, try to update your code and report on what happens.