title: Failed to start the Kernel. Cannot run Jupyter Notebook in VS Code for Windows. Issue with Traitlets
body: <p>I am trying to run a Jupyter Notebook in VS Code for Windows and running into an issue with traitlets. Can anyone help?</p>
  <p>Following steps to re-create:</p>
  <ol>
  <li>Start new Python virtual environment.</li>
  <li>Create new Jupyter Notebook (.ipynb file)</li>
  <li>Open file in VS Code for Windows and select virtual environment's interpreter.</li>
  <li>Try and run <code>print('hello')</code> in the first kernel.</li>
  </ol>
  <p>The error message I get:</p>
  <pre><code>Failed to start the Kernel. 
  c:\Users\XX\python_projects\demo_issue\myenv\lib\site-packages\traitlets\traitlets.py:2202: FutureWarning: Supporting extra quotes around strings is deprecated in traitlets 5.0. You can use 'hmac-sha256' instead of '&quot;hmac-sha256&quot;' if you require traitlets &gt;=5.
    warn(
  c:\Users\XX\python_projects\demo_issue\myenv\lib\site-packages\traitlets\traitlets.py:2157: FutureWarning: Supporting extra quotes around Bytes is deprecated in traitlets 5.0. Use '7518421c-2675-406f-81c8-3e4a669b0c20' instead of 'b&quot;7518421c-2675-406f-81c8-3e4a669b0c20&quot;'.
    warn(
  Bad file descriptor (C:\projects\libzmq\src\epoll.cpp:100). 
  View Jupyter log for further details.
  </code></pre>
  <p>I have tried to install an earlier version of traitlets (<code>python -m pip install traitlets&lt;5 --force-reinstall</code>) but it creates dependency conflicts:</p>
  <pre><code>ERROR: pip's dependency resolver does not currently take into account all the packages that are installed. This behaviour is the source of the following dependency conflicts.
  ipython 8.3.0 requires traitlets&gt;=5, but you have traitlets 4.3.3 which is incompatible.
  ipykernel 6.13.0 requires traitlets&gt;=5.1.0, but you have traitlets 4.3.3 which is incompatible.
  </code></pre>
  <p>And I also get this error under the kernel:</p>
  <pre><code>The file 'myenv\lib\site-packages\traitlets\utils\__init__.py' seems to be overriding built in modules and interfering with the startup of the kernel. Consider renaming the file and starting the kernel again.
  Click here for more info.
  </code></pre>
  <p>Here is a screenshot of the main issue, in case helpful.
  <a href="https://i.stack.imgur.com/tNdiL.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/tNdiL.png" alt="enter image description here" /></a></p>
  <p>Does anyone how any ideas of how I might fix? What am I doing wrong?</p>
  <p>Thank you for any help you can give!</p>