How to display gui using python based app

I am getting following error while running snap

alphaict@localhost:~$ alphasnapotatest
Traceback (most recent call last):
File “/snap/alphasnapotatest/x1/bin/alphatest”, line 33, in
sys.exit(load_entry_point(‘alphatest==1.0’, ‘console_scripts’, ‘alphatest’)())
File “/snap/alphasnapotatest/x1/lib/python3.5/site-packages/src/app.py”, line 9, in main
fieldValues = multenterbox(msg, title, fieldNames)
File “/snap/alphasnapotatest/x1/lib/python3.5/site-packages/easygui/boxes/multi_fillable_box.py”, line 133, in multenterbox
callback=callback)
File “/snap/alphasnapotatest/x1/lib/python3.5/site-packages/easygui/boxes/multi_fillable_box.py”, line 186, in init
mask_last, self.callback_ui)
File “/snap/alphasnapotatest/x1/lib/python3.5/site-packages/easygui/boxes/multi_fillable_box.py”, line 268, in init
self.boxRoot = tk.Tk()
File “/snap/alphasnapotatest/x1/usr/lib/python3.5/tkinter/init.py”, line 1871, in init
self.tk = _tkinter.create(screenName, baseName, className, interactive, wantobjects, useTk, sync, use)
_tkinter.TclError: no display name and no $DISPLAY environment variable

please give suggestion as soon as possible
thanks in advance