Its a Python standard library [function](https://docs.python.org/3/library/curses.html?highlight=rectangle#curses.tex...) and it comes from the global symbols which are automatically loaded when a Python file is loaded, see a message like
` Geany INFO : Loaded /XXXXXXXX/share/geany/tags/std.py.tags (Python), 5963 symbol(s).`
in `Help->Debug Messages`
Unfortunately there is no way of defining priorities for symbols, we just had a major effort to get Geany to attempt some heuristics for C++ to make a better choice, but they are hard coded and specific to C/C++. Thats not a sustainable model for the number of languages Geany supports, but I can't see how a configurable model would work either. Suggestions welcome.