Hi @kot,
does running the code with python -i (note the -i) solve the issue?
What if you run those lines in the interactive interpreter rather than in a script? Also if you are on lxplus did you connect with ssh -XY to get X11 forwarding? Are there warnings or errors printed on screen?
Python is run in an interactive mode, not as a script.
I connect to lxplus via MobaXterm with enabled X11-forwarding. Please note it works fine with ROOT 6.14.04.
No warnings, either errors are thrown