def METHOD_NAME(self, authorization_url, extra_params):
    """
    Returns a ``HttpResponseRedirect`` object to redirect the user
    to the URL the OAuth provider handles authorization.
    """
    request_token = self._get_request_token()
    params = {
        "oauth_token": request_token["oauth_token"],
        "oauth_callback": self.request.build_absolute_uri(self.callback_url),
    }
    params.update(extra_params)
    url = authorization_url + "?" + urlencode(params)
    return HttpResponseRedirect(url)