The demo problem

[LeeHY-1]

Hello, I tried to run the demo.py, but the output is as follows：

The X11 connection broke: No error (code 0)
XIO: fatal IO error 22 (Invalid argument) on X server "localhost:10.0"
after 400 requests (400 known processed) with 0 events remaining.

And I found it happened after this line:
viz = poseviz.PoseViz(joint_names, joint_edges)

How to solve it?
My operating system is Ubuntu 18.04.5 LTS.

[isarandi]

This is unlikely to be specific about code in this repo.