AttributeError: 'NoneType' object has no attribute 'startswith' from get_user with 403 response #2158
Description
Looks like the same root issue as #1399 but that was closed and I can't re-open it (not sure why it was closed).
This is with pygithub 1.55:
File "/home/travis/virtualenv/python3.8.1/lib/python3.8/site-packages/github/MainClass.py", line 256, in get_user
headers, data = self.__requester.requestJsonAndCheck(
File "/home/travis/virtualenv/python3.8.1/lib/python3.8/site-packages/github/Requester.py", line 353, in requestJsonAndCheck
return self.__check(
File "/home/travis/virtualenv/python3.8.1/lib/python3.8/site-packages/github/Requester.py", line 378, in __check
raise self.__createException(status, responseHeaders, output)
File "/home/travis/virtualenv/python3.8.1/lib/python3.8/site-packages/github/Requester.py", line 418, in __createException
elif status == 403 and output.get("message").startswith(
AttributeError: 'NoneType' object has no attribute 'startswith'