All the buildbots are currently failing at test_nntplib.
See the errors in attached test_nntplib.log.
The same error messages can be reproduced with a 3.5.2 interpreter:

$ python
Python 3.5.2 (default, Nov  7 2016, 11:31:36)
[GCC 6.2.1 20160830] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> from nntplib import NNTP_SSL
>>> s = NNTP_SSL('nntp.aioe.org')
>>> resp, count, first, last, name = s.group('comp.lang.python')
>>> resp, overviews = s.over((last - 1, last))                      # does not fail
>>> resp, overviews = s.over((last - 9, last))
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/lib/python3.5/nntplib.py", line 831, in over
    resp, lines = self._longcmdstring(cmd, file)
  File "/usr/lib/python3.5/nntplib.py", line 525, in _longcmdstring
    resp, list = self._getlongresp(file)
  File "/usr/lib/python3.5/nntplib.py", line 494, in _getlongresp
    line = self._getline()
  File "/usr/lib/python3.5/nntplib.py", line 434, in _getline
    raise NNTPDataError('line too long')
nntplib.NNTPDataError: line too long
>>> resp, overviews = s.over((last - 1, last))                      # fails now
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/lib/python3.5/nntplib.py", line 831, in over
    resp, lines = self._longcmdstring(cmd, file)
  File "/usr/lib/python3.5/nntplib.py", line 525, in _longcmdstring
    resp, list = self._getlongresp(file)
  File "/usr/lib/python3.5/nntplib.py", line 476, in _getlongresp
    resp = self._getresp()
  File "/usr/lib/python3.5/nntplib.py", line 458, in _getresp
    raise NNTPProtocolError(resp)
nntplib.NNTPProtocolError: a657tKkPSmKkOzCP9RkpDChwanytHhX4XFYLLMWqmA@mail.gmail.com> <CANc-5UxXPRF3qYKEmnyDdANoN-5GLiRXDrOU6E=R-8N8ZV2UdQ@mail.gmail.com> <CANc-5UwNFgS4aFN5qbwOPNdTMfXrEpJrv4b00_ycGmwAAoK81Q@mail.gmail.com> <CANc-5UyhtmjE9rXwhMBx=H9tBmYARhfzVjw2O=iKDmyEdCpqSA@mail.gmail.com> <CANc-5UyHLP3W8-_D18f8qE-9z0Y-DMbuHRMLpLY10eA52YZMew@mail.gmail.com> <CANc-5UxQA=-9Q=1GPh+5epX9E3KbAgd6Ye_63=kB55aB-MHqow@mail.gmail.com> <CANc-5UwqKjfxrxS0tvSk6r0kRQbr5kiAyCxJhUT8JPfcySSG2A@mail.gmail.com>
<CANc-5Uyj9VnJbVGSepVLLHeCgoB9uAOD61Ft4b=bdLTQJ5dE=A@mail.gmail.com>    10039   25      Xref: aioe.org comp.lang.python:183369