Simon Nicolussi added the comment:
Requests 1.2.1 has been released to address this issue. An origin_req_host
property has been added to the request object as a workaround.
The original problem of mismatched documentation and behaviour still persists
New submission from Simon Nicolussi:
A fix for a DeprecationWarning (#17678) had the unfortunate side effect of
changing the expected interface of the request object higher up in the call
stack.
For example, the documentation for CookieJar.add_cookie_header(request) states
that the request
