title: Werkzeug server is shutting down in Django application
body: <p>after updating the Werkzeug version from 2.0.3 to 2.1.0, I keep getting errors every time I run the server, and here is the error log:</p>
  <pre><code>Exception happened during processing of request from ('127.0.0.1', 44612)                                                                                                                                  
  Traceback (most recent call last):                                                                                                                                                                         
    File &quot;/usr/lib/python3.8/socketserver.py&quot;, line 683, in process_request_thread                                                                                                                           
      self.finish_request(request, client_address)                                                                                                                                                           
    File &quot;/usr/lib/python3.8/socketserver.py&quot;, line 360, in finish_request                                                                                                                                   
      self.RequestHandlerClass(request, client_address, self)                                                                                                                                                
    File &quot;/usr/lib/python3.8/socketserver.py&quot;, line 747, in __init__                                                                                                                                         
      self.handle()                                                                                                                                                                                          
    File &quot;/home/oladhari/.virtualenvs/reachat/lib/python3.8/site-packages/werkzeug/serving.py&quot;, line 363, in handle                                                                                          
      super().handle()                                                                                                                                                                                       
    File &quot;/usr/lib/python3.8/http/server.py&quot;, line 427, in handle                                                                                                                                            
      self.handle_one_request()                                                                                                                                                                              
    File &quot;/usr/lib/python3.8/http/server.py&quot;, line 415, in handle_one_request                                                                                                                                
      method()                                                                                                                                                                                               
    File &quot;/home/oladhari/.virtualenvs/reachat/lib/python3.8/site-packages/werkzeug/serving.py&quot;, line 243, in run_wsgi                                                                                        
      self.environ = environ = self.make_environ()                                                                                                                                                           
    File &quot;/home/oladhari/.virtualenvs/reachat/lib/python3.8/site-packages/django_extensions/management/commands/runserver_plus.py&quot;, line 326, in make_environ                                                
      del environ['werkzeug.server.shutdown']                                                                                                                                                                
  KeyError: 'werkzeug.server.shutdown'  
  </code></pre>
  <p>this exception keep appearing while incrementing by 2 ( ('127.0.0.1', 44612) -&gt;  ('127.0.0.1', 44628)  and the server crash</p>
  <p>checking the changes log, I have found this detail:</p>
  <pre><code>Remove previously deprecated code. #2276
  
  Remove the non-standard shutdown function from the WSGI environ when running the development server. See the docs for alternatives.
  </code></pre>
  <p>here is the link to the <a href="https://werkzeug.palletsprojects.com/en/2.1.x/changes/#version-2-1-0" rel="noreferrer">changes log</a></p>
  <p>it asks to check the <a href="https://werkzeug.palletsprojects.com/en/2.1.x/" rel="noreferrer">documentation</a> for alternatives but can not find any</p>
  <p>please let me know how I would resolve this error, thank you
  NB: my python version is 3.8</p>