clean installation fails with python "TypeError: a bytes-like object is required, not 'str'"

[Bart N]

First (clean) installation already fails with two errors.
This is the scenario i followed:

- Pi B+ V1.2,
- Raspbian 4.9.41+ (did an update and upgrade prior to installing WebIOPi)
- WebIOPi 0.7.1 (installed using tar, that installed Python 3.5)
- starting for the first time (as suggested in the installation page)    
    $ sudo webiopi -d -c /etc/webiopi/config

Opening for first time from the webbrowser generates following two errors (repeatedly) on the terminal.
Both seem Python generated errors.

Should i configure python somewhere, or is this related to the update issue for the Pi B+?


...
2018-01-02 18:52:37 - WbIOPi - INFO - CoAP Server binded on coap://224.0.1.123:5683/ (MULTICAST)
----------------------------------------------------------
Exception happened during processing of request from ('::1', 34584, 0, 0)
Traceback (most recent call last):
   File " /usr/lib/python3.5/dist-packages/WebIOPi-0.7.1-py3.5-linux-armv61.egg/webiopi/protocols/http.py", line 254, in processRequest
      self.serveFile(relativePath)
...
TypeError: a bytes-like object is required, not 'str'

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
...
NameError: name ' GPIO' is not defined

[hal8000b]

You have exactly same error as me now. The problem is with Python3.5 branch was working with 3.4. My OSMC box did
an update and uses python 3.5 . Have to go to work now but will be looking for a solution when I get home.