Periodically I try to run the example (my computer: Windows 10, browser: Google Chrome):
pytorch.org -> Tutorials -> Reinforcement Learning -> Reinforcement Learning (DQN) Tutorial -> Run in Google Colab -> menu Runtime -> menu item Run All.
But I always get such error:
NoSuchDisplayException                    Traceback (most recent call last)
 in ()
39 env.reset()
40 plt.figure()
—> 41 plt.imshow(get_screen().cpu().squeeze(0).permute(1, 2, 0).numpy(),
42            interpolation=‘none’)
43 plt.title(‘Example extracted screen’)
9 frames
/usr/local/lib/python3.6/dist-packages/pyglet/canvas/xlib.py in init(self, name, x_screen)
121         self._display = xlib.XOpenDisplay(name)
122         if not self._display:
–> 123             raise NoSuchDisplayException(‘Cannot connect to “%s”’ % name)
124
125         screen_count = xlib.XScreenCount(self._display)
NoSuchDisplayException: Cannot connect to “None”