title: Get RuntimeWarning when running Jupyter notebook and never connects to Kernel
body: <p>I have a fresh install of python 3.7.2 and pip installed jupyter 4.4.0 in a fresh venv on Windows 7.0 professional.
  I started a Jupyter notebook and my notebook never connects to the kernel.
  On the command prompt, I see this error:</p>
  
  <pre><code>[I 17:41:11.959 NotebookApp] Kernel started: 35b03148-7d3e-48cb-a270-ebe959012d98
  [I 17:41:14.307 NotebookApp] Adapting to protocol v5.1 for kernel 35b03148-7d3e-48cb-a270-ebe959012d98
  &lt;full path masked&gt;...\py372venv\lib\site-packages\notebook\base\zmqhandlers.py:284: RuntimeWarning: coroutine 'WebSocketHandler.get' was never awaited
    super(AuthenticatedZMQStreamHandler, self).get(*args, **kwargs)
  RuntimeWarning: Enable tracemalloc to get the object allocation traceback
  [W 17:41:15.404 NotebookApp] Replacing stale connection: 35b03148-7d3e-48cb-a270-ebe959012d98:3b9a037fced84ccc891192e2f387bae0
  [W 17:41:37.415 NotebookApp] Replacing stale connection: 35b03148-7d3e-48cb-a270-ebe959012d98:3b9a037fced84ccc891192e2f387bae0
  [W 17:42:01.421 NotebookApp] Replacing stale connection: 35b03148-7d3e-48cb-a270-ebe959012d98:3b9a037fced84ccc891192e2f387bae0
  [W 17:42:29.468 NotebookApp] Replacing stale connection: 35b03148-7d3e-48cb-a270-ebe959012d98:3b9a037fced84ccc891192e2f387bae0
  [W 17:43:05.489 NotebookApp] Replacing stale connection: 35b03148-7d3e-48cb-a270-ebe959012d98:3b9a037fced84ccc891192e2f387bae0
  </code></pre>
  
  <p>These replacing stale connection messages continue.
  What could be the issue? I am new to Jupyter and a bit less new to Python.</p>