I've tried to install both python2 and python3 kernels as suggested here and here (through pip and pip3 ipykernel install), but in all the variants I end up with working python2 kernel and almost-working python3 one.
python3 kernel is displayed as the option in "New" dropdown menu, but all notebooks created under it don't produce any output.
That is, I can create new cell, paste print(5) in there and run it (the runcount to the left will be incremented), but no output cell is produced.
Same (no) reaction is observed on syntactically-wrong code.
Any ideas on where to go?