I followed exactly instructions in python plugin readme, but still can not run demo plugin ucharmap.py

0. sudo apt install virtualenv (I already had python 3.8 installed)
1. Build with "-DPYTHON=yes" (build completed successfully)
2. Copied ucharmap.py to ~/.config/far2l/plugins/python
3. Run "py: load ucharmap" (no reaction, no error notification, no success notification)
4. F11 menu still lacks "Python Character Map"

Log attached
far2l-py.log