I think this is an issue with wsgiref handling client closure rather than a Windows/Django bug. I saw this sporadically but not consistently while running `make serve` to serve the docs which uses wsgiref simple server to serve docs on my Mac OS. Related issue34547 with a PR that catches ConnectionAbortedError and returns.

PR link : https://github.com/python/cpython/pull/9713/

Sample traceback while serving docs locally with `make serve` on Mac OS: 

127.0.0.1 - - [12/Oct/2018 10:56:57] "GET /_sources/library/asyncio-eventloop.rst.txt HTTP/1.1" 500 59
----------------------------------------
Exception happened during processing of request from ('127.0.0.1', 50436)
Traceback (most recent call last):
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/wsgiref/handlers.py", line 138, in run
    self.finish_response()
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/wsgiref/handlers.py", line 180, in finish_response
    self.write(data)
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/wsgiref/handlers.py", line 274, in write
    self.send_headers()
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/wsgiref/handlers.py", line 332, in send_headers
    self.send_preamble()
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/wsgiref/handlers.py", line 255, in send_preamble
    ('Date: %s\r\n' % format_date_time(time.time())).encode('iso-8859-1')
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/wsgiref/handlers.py", line 453, in _write
    result = self.stdout.write(data)
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/socketserver.py", line 796, in write
    self._sock.sendall(b)
BrokenPipeError: [Errno 32] Broken pipe

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/wsgiref/handlers.py", line 141, in run
    self.handle_error()
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/wsgiref/handlers.py", line 368, in handle_error
    self.finish_response()
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/wsgiref/handlers.py", line 180, in finish_response
    self.write(data)
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/wsgiref/handlers.py", line 274, in write
    self.send_headers()
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/wsgiref/handlers.py", line 331, in send_headers
    if not self.origin_server or self.client_is_modern():
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/wsgiref/handlers.py", line 344, in client_is_modern
    return self.environ['SERVER_PROTOCOL'].upper() != 'HTTP/0.9'
TypeError: 'NoneType' object is not subscriptable

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/socketserver.py", line 313, in _handle_request_noblock
    self.process_request(request, client_address)
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/socketserver.py", line 344, in process_request
    self.finish_request(request, client_address)
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/socketserver.py", line 357, in finish_request
    self.RequestHandlerClass(request, client_address, self)
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/socketserver.py", line 717, in __init__
    self.handle()
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/wsgiref/simple_server.py", line 133, in handle
    handler.run(self.server.get_app())
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/wsgiref/handlers.py", line 144, in run
    self.close()
  File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/wsgiref/simple_server.py", line 35, in close
    self.status.split(' ',1)[0], self.bytes_sent
AttributeError: 'NoneType' object has no attribute 'split'


Thanks