I am trying to set up this project on Python 3.7, ubuntu 20.04.1 LTS. When I run gbr2.py I get the following error
Traceback (most recent call last): File "gbr2.py", line 1301, in <module> main() File "gbr2.py", line 1294, in main window = GbrGUI2() File "gbr2.py", line 932, in __init__ tk.Tk.__init__(self, "Go board") File "/usr/lib/python3.8/tkinter/__init__.py", line 2261, in __init__ self.tk = _tkinter.create(screenName, baseName, className, interactive, wantobjects, useTk, sync, use) _tkinter.TclError: couldn't connect to display "Go board"

Do you know what the issue could be?