Need tests of turtledemo.colordemo on Windows installations

[Terry Reedy]

User Tushar Sadhwani and I both have Win 10 with 3.8.5 installed.  When 
he runs
...> py -3.8 -m turtledemo.colormixer
and moves the sliders a reasonable amount, he repeatably gets
Fatal Python error: Cannot recover from stack overflow.
...
https://bugs.python.org/issue41758

I have no problem, regardless of version, PowerShell or Command Prompt, 
installation or repository build.  I suspect that the issue is specific 
to his machine, but before closing, we need more evidence either way.

-- 
Terry Jan Reedy