Why does Tkinter._test() run in one case and not in the other?

Question

Python

I decided to try out such a thing on my Windows 7 https://habrahabr.ru/post/266441/
I downloaded Cygwin by additionally installing the Tkinter 8.5 package for Python2.7.10 to it, but I ran into an elementary problem. When I run Python on Cygwin I do the following:

import Tkinter
Tkinter._test()

and the window does not pop up, but I get the answer:

_tkinter.TclError: no display name and no $DISPLAY environment variable

For comparison, I had Python2.7.11 on Windows itself, where I decided to try the above commands and everything worked out. Tkinter is imported and after the test, a small window pops up with the version.
Help good people?
PS Google has already traveled far and wide. Well, no one had such problems, and if they did, they were not documented.

Answer 1

You obviously have some kind of problem with Xwindows. Set your error as a Google search criterion and try the suggested options. Well, and Cygwin, it's not exactly Linux. Try better on a "normal" Linux'e in a virtual machine.