django-sslserver: AttributeError: 'NoneType' object has no attribute 'split'

I’m running Python 3.5 and Django 2.0.2.

After installing django-sslserver, I’m seeing an exception whenever there’s any sort of POST to my localhost server. It doesn’t yet seem to be causing any problems, but any advice would be appreciated.

Here’s the traceback:

Traceback (most recent call last):
  File "/usr/lib/python3.5/wsgiref/handlers.py", line 138, in run
    self.finish_response()
  File "/usr/lib/python3.5/wsgiref/handlers.py", line 180, in finish_response
    self.write(data)
  File "/usr/lib/python3.5/wsgiref/handlers.py", line 279, in write
    self._write(data)
  File "/usr/lib/python3.5/wsgiref/handlers.py", line 453, in _write
    result = self.stdout.write(data)
  File "/usr/lib/python3.5/socket.py", line 593, in write
    return self._sock.send(b)
  File "/usr/lib/python3.5/ssl.py", line 861, in send
    return self._sslobj.write(data)
  File "/usr/lib/python3.5/ssl.py", line 586, in write
    return self._sslobj.write(data)
ssl.SSLEOFError: EOF occurred in violation of protocol (_ssl.c:1844)
----------------------------------------
Exception happened during processing of request from ('127.0.0.1', 46760)
Traceback (most recent call last):
  File "/usr/lib/python3.5/wsgiref/handlers.py", line 138, in run
    self.finish_response()
  File "/usr/lib/python3.5/wsgiref/handlers.py", line 180, in finish_response
    self.write(data)
  File "/usr/lib/python3.5/wsgiref/handlers.py", line 279, in write
    self._write(data)
  File "/usr/lib/python3.5/wsgiref/handlers.py", line 453, in _write
    result = self.stdout.write(data)
  File "/usr/lib/python3.5/socket.py", line 593, in write
    return self._sock.send(b)
  File "/usr/lib/python3.5/ssl.py", line 861, in send
    return self._sslobj.write(data)
  File "/usr/lib/python3.5/ssl.py", line 586, in write
    return self._sslobj.write(data)
ssl.SSLEOFError: EOF occurred in violation of protocol (_ssl.c:1844)

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/lib/python3.5/wsgiref/handlers.py", line 141, in run
    self.handle_error()
  File "/home/user/git_projects/django/env/lib/python3.5/site-packages/django/core/servers/basehttp.py", line 86, in handle_error
    super().handle_error()
  File "/usr/lib/python3.5/wsgiref/handlers.py", line 368, in handle_error
    self.finish_response()
  File "/usr/lib/python3.5/wsgiref/handlers.py", line 180, in finish_response
    self.write(data)
  File "/usr/lib/python3.5/wsgiref/handlers.py", line 274, in write
    self.send_headers()
  File "/usr/lib/python3.5/wsgiref/handlers.py", line 331, in send_headers
    if not self.origin_server or self.client_is_modern():
  File "/usr/lib/python3.5/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 "/usr/lib/python3.5/socketserver.py", line 313, in _handle_request_noblock
    self.process_request(request, client_address)
  File "/usr/lib/python3.5/socketserver.py", line 341, in process_request
    self.finish_request(request, client_address)
  File "/usr/lib/python3.5/socketserver.py", line 354, in finish_request
    self.RequestHandlerClass(request, client_address, self)
  File "/usr/lib/python3.5/socketserver.py", line 681, in __init__
    self.handle()
  File "/home/user/git_projects/django/env/lib/python3.5/site-packages/django/core/servers/basehttp.py", line 154, in handle
    handler.run(self.server.get_app())
  File "/usr/lib/python3.5/wsgiref/handlers.py", line 144, in run
    self.close()
  File "/usr/lib/python3.5/wsgiref/simple_server.py", line 36, in close
    self.status.split(' ',1)[0], self.bytes_sent
AttributeError: 'NoneType' object has no attribute 'split'
----------------------------------------