-O option broken with HTTP redirects

[tylerknott]

For example, wpull -O x http://www.ncbi.nlm.nih.gov/pubmed/16713885 (which redirects to https://www.ncbi.nlm.nih.gov/pubmed/16713885) outputs the following:

INFO Fetching ‘http://www.ncbi.nlm.nih.gov/pubmed/16713885’.
100.0% [=========================] 252.0 B 0:00:00 1.0 KiB/s
INFO Fetched ‘http://www.ncbi.nlm.nih.gov/pubmed/16713885’: 301 Moved Permanently. Length: 252 [text/html; charset=iso-8859-1].
INFO Fetching ‘https://www.ncbi.nlm.nih.gov/pubmed/16713885’.
/usr/local/lib/python3.4/dist-packages/wpull/protocol/http/client.py:185: UserWarning: HTTP session did not complete.
warnings.warn(_('HTTP session did not complete.'))
ERROR Fatal exception.
Traceback (most recent call last):
File "/usr/local/lib/python3.4/dist-packages/wpull/application/app.py", line 152, in run
yield from pipeline.process()
File "/usr/local/lib/python3.4/dist-packages/wpull/pipeline/pipeline.py", line 194, in process
yield from self._process_one_worker()
File "/usr/local/lib/python3.4/dist-packages/wpull/pipeline/pipeline.py", line 215, in _process_one_worker
task.result()
File "/usr/lib/python3.4/asyncio/futures.py", line 277, in result
raise self._exception
File "/usr/lib/python3.4/asyncio/tasks.py", line 235, in _step
result = coro.send(value)
File "/usr/local/lib/python3.4/dist-packages/wpull/pipeline/pipeline.py", line 119, in process
item = yield from self.process_one(_worker_id=worker_id)
File "/usr/local/lib/python3.4/dist-packages/wpull/pipeline/pipeline.py", line 103, in process_one
yield from task.process(item)
File "/usr/local/lib/python3.4/dist-packages/wpull/application/tasks/download.py", line 492, in process
yield from session.app_session.factory['Processor'].process(session)
File "/usr/local/lib/python3.4/dist-packages/wpull/processor/delegate.py", line 29, in process
return (yield from processor.process(item_session))
File "/usr/local/lib/python3.4/dist-packages/wpull/processor/web.py", line 92, in process
return (yield from session.process())
File "/usr/local/lib/python3.4/dist-packages/wpull/processor/web.py", line 186, in process
yield from self._process_loop()
File "/usr/local/lib/python3.4/dist-packages/wpull/processor/web.py", line 245, in _process_loop
exit_early, wait_time = yield from self._fetch_one(cast(Request, self._item_session.request))
File "/usr/local/lib/python3.4/dist-packages/wpull/processor/web.py", line 276, in _fetch_one
self._file_writer_session.process_response(response)
File "/usr/local/lib/python3.4/dist-packages/wpull/writer.py", line 511, in process_response
if not self._stream.readable():
ValueError: I/O operation on closed file
CRITICAL Sorry, Wpull unexpectedly crashed.
CRITICAL Please report this problem to the authors at Wpull's issue tracker so it may be fixed. If you know how to program, maybe help us fix it? Thank you for helping us help you help us all.
INFO Exiting with status 1.

Downloading the URL without -O or downloading the https version of the URL both work correctly. This is with version 2.0.1 running on Python 3.4.2 on 32-bit Debian Jessie.