Closes: https://bugs.debian.org/944194
get_full_url() was changed to full_url by
https://github.com/python/cpython/commit/6c5e28c383bf587f80d01e52f887801be200200d
(3.1).
headers.get() was changed to get_header() by
https://github.com/python/cpython/commit/783737625d1f06f78b53eee6331d2f428ffe4d27
(3.4)