IDLE/Tkinter Error: no display name and no $DISPLAY environment variable

Traceback (most recent call last):  File "/usr/bin/idle", line 5, in \<module\>    main()  File "/usr/lib/python3.10/idlelib/pyshell.py", line 1617, in main    root = Tk(className="Idle")  File "/usr/lib/python3.10/tkinter/__init__.py", line 2299, in __init__    self.tk = _tkinter.create(screenName, baseName, className, interactive, wantobjects, useTk, sync, use)_tkinter.TclError: no display name and no $DISPLAY environment variable

When i used idle command for writing python in idle, i got this system message. I don't know what's that mean. I'm so new for ubuntu. I hope someone know this answer.