capture() does not work on Sony a7r3

[chubun]

I tried the sample code on a Sony a7r3:

import gphoto2cffi as gp
my_cam = gp.Camera()
imgdata = my_cam.capture()

And get the following error:

Traceback (most recent call last):
File "", line 1, in
File "/home/installer/.local/lib/python3.6/site-packages/gphoto2cffi/gphoto2.py", line 105, in wrapped
rval = meth(self, *args, **kwargs)
File "/home/installer/.local/lib/python3.6/site-packages/gphoto2cffi/gphoto2.py", line 716, in capture
target = self.config['settings']['capturetarget']
KeyError: 'capturetarget'

In the debugger:

len(my_cam.config['settings'])
0

By the way, the output from
gphoto2 --list-config
does not show a "/main/settings" section, only "/main/capturesettings/", "/main/actions/", ...

However, I have no problems capturing images using gphoto2 or python-gphoto2.