`None` returned in successful token revocation body

[Geekfish]

In oauthlib the revocation handler does the following:

def create_revocation_response(self, uri, http_method='POST', body=None, headers=None):
    # ... more stuff here ...
    response_body = request.callback + '()' if request.callback else None
    return {}, response_body, 200

Then the tuple response eventually reaches the wrapper view and an HttpResponse is created:

def post(self, request, *args, **kwargs):
    url, headers, body, status = self.create_revocation_response(request)
    response = HttpResponse(content=body, status=status)
    # ... more stuff here ...
    return response

The result in case of success, when there isn't a callback, is a response body that just contains None.

HTTP/1.1 200 OK
Content-Type: text/html

None

I think that the response body should be completely empty, None makes sense as a python type but it's meaningless for an api consumer that will just treat it as text.