What’s the simplest cross-platform way to pop up graphical dialogs in Python?

Question

EasyGUI is a single file, and provides a simple way to work with Tkinter dialogs, but they’re still ugly non-native Tkinter dialogs.

from easygui import msgbox
msgbox('Stuff')

Tkinter is ugly on Ubuntu
TKinter is ugly on Windows 7

It can easily be installed using:

$ sudo pip3 install --upgrade easygui

There is a GitHub repository and documentation is very neat.

Previously, there was also a fork called EasyGuiTtk, which unfortunately is no longer available.

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