Error when run reinforcement_q_learning.ipynb

tv76: <p>Periodically I try to run the example (my computer: Windows 10, browser: Google Chrome):</p>
<p><a href="http://pytorch.org" rel="nofollow noopener">pytorch.org</a> -&gt; Tutorials -&gt; Reinforcement Learning -&gt; Reinforcement Learning (DQN) Tutorial -&gt; Run in Google Colab -&gt; menu Runtime -&gt; menu item Run All.</p>
<h2>But I always get such error:</h2>
<p>NoSuchDisplayException                    Traceback (most recent call last)<br>
 in ()<br>
39 env.reset()<br>
40 plt.figure()<br>
—&gt; 41 plt.imshow(get_screen().cpu().squeeze(0).permute(1, 2, 0).numpy(),<br>
42            interpolation=‘none’)<br>
43 plt.title(‘Example extracted screen’)</p>
<p>9 frames<br>
/usr/local/lib/python3.6/dist-packages/pyglet/canvas/xlib.py in <strong>init</strong>(self, name, x_screen)<br>
121         self._display = xlib.XOpenDisplay(name)<br>
122         if not self._display:<br>
–&gt; 123             raise NoSuchDisplayException(‘Cannot connect to “%s”’ % name)<br>
124<br>
125         screen_count = xlib.XScreenCount(self._display)</p>
<p>NoSuchDisplayException: Cannot connect to “None”</p>

ptrblck: <p>It seems to be a known issue (<a href="https://discuss.pytorch.org/t/found-bug-in-pytorch-reinforcement-tutorials/73554/9">related post</a>).<br>
I can’t find an issue, so I assume the other user didn’t create one.<br>
Would you mind creating the issue for this tutorial?<br>
If not, please let me know, and I’ll do it.</p>

tv76: <p>Oh, sure:<br>
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      <a href="https://github.com/pytorch/tutorials/issues/915" target="_blank" rel="nofollow noopener">Error when run reinforcement_q_learning.ipynb</a>
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        opened <span class="discourse-local-date" data-format="ll" data-date="2020-03-30" data-time="07:38:41" data-timezone="UTC">07:38AM - 30 Mar 20 UTC</span>
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  <p class="github-content">Periodically I try to run the example (my computer: Windows 10, browser: Google Chrome):
pytorch.org -&gt; Tutorials -&gt; Reinforcement Learning -&gt; Reinforcement...</p>
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