Exception:
Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/pip/basecommand.py", line 215, in main
    status = self.run(options, args)
  File "/usr/lib/python3/dist-packages/pip/commands/install.py", line 353, in run
    wb.build(autobuilding=True)
  File "/usr/lib/python3/dist-packages/pip/wheel.py", line 749, in build
    self.requirement_set.prepare_files(self.finder)
  File "/usr/lib/python3/dist-packages/pip/req/req_set.py", line 380, in prepare_files
    ignore_dependencies=self.ignore_dependencies))
  File "/usr/lib/python3/dist-packages/pip/req/req_set.py", line 620, in _prepare_file
    session=self.session, hashes=hashes)
  File "/usr/lib/python3/dist-packages/pip/download.py", line 821, in unpack_url
    hashes=hashes
  File "/usr/lib/python3/dist-packages/pip/download.py", line 659, in unpack_http_url
    hashes)
  File "/usr/lib/python3/dist-packages/pip/download.py", line 882, in _download_http_url
    _download_url(resp, link, content_file, hashes)
  File "/usr/lib/python3/dist-packages/pip/download.py", line 603, in _download_url
    hashes.check_against_chunks(downloaded_chunks)
  File "/usr/lib/python3/dist-packages/pip/utils/hashes.py", line 46, in check_against_chunks
    for chunk in chunks:
  File "/usr/lib/python3/dist-packages/pip/download.py", line 571, in written_chunks
    for chunk in chunks:
  File "/usr/lib/python3/dist-packages/pip/utils/ui.py", line 139, in iter
    for x in it:
  File "/usr/lib/python3/dist-packages/pip/download.py", line 560, in resp_read
    decode_content=False):
  File "/usr/share/python-wheels/urllib3-1.22-py2.py3-none-any.whl/urllib3/response.py", line 436, in stream
    data = self.read(amt=amt, decode_content=decode_content)
  File "/usr/share/python-wheels/urllib3-1.22-py2.py3-none-any.whl/urllib3/response.py", line 384, in read
    data = self._fp.read(amt)
  File "/usr/share/python-wheels/CacheControl-0.11.7-py2.py3-none-any.whl/cachecontrol/filewrapper.py", line 63, in read
    self._close()
  File "/usr/share/python-wheels/CacheControl-0.11.7-py2.py3-none-any.whl/cachecontrol/filewrapper.py", line 50, in _close
    self.__callback(self.__buf.getvalue())
  File "/usr/share/python-wheels/CacheControl-0.11.7-py2.py3-none-any.whl/cachecontrol/controller.py", line 275, in cache_response
    self.serializer.dumps(request, response, body=body),
  File "/usr/share/python-wheels/CacheControl-0.11.7-py2.py3-none-any.whl/cachecontrol/serialize.py", line 86, in dumps
    data, separators=(",", ":"), sort_keys=True,
  File "/usr/lib/python3.6/json/__init__.py", line 238, in dumps
    **kw).encode(obj)
  File "/usr/lib/python3.6/json/encoder.py", line 199, in encode
    chunks = self.iterencode(o, _one_shot=True)
  File "/usr/lib/python3.6/json/encoder.py", line 257, in iterencode
    return _iterencode(o, 0)
MemoryError

Exception:
Traceback (most recent call last):
  File "/usr/share/python-wheels/urllib3-1.22-py2.py3-none-any.whl/urllib3/response.py", line 302, in _error_catcher
    yield
  File "/usr/share/python-wheels/urllib3-1.22-py2.py3-none-any.whl/urllib3/response.py", line 384, in read
    data = self._fp.read(amt)
  File "/usr/lib/python3.6/http/client.py", line 449, in read
    n = self.readinto(b)
  File "/usr/lib/python3.6/http/client.py", line 493, in readinto
    n = self.fp.readinto(b)
  File "/usr/lib/python3.6/socket.py", line 586, in readinto
    return self._sock.recv_into(b)
  File "/usr/lib/python3.6/ssl.py", line 1012, in recv_into
    return self.read(nbytes, buffer)
  File "/usr/lib/python3.6/ssl.py", line 874, in read
    return self._sslobj.read(len, buffer)
  File "/usr/lib/python3.6/ssl.py", line 631, in read
    v = self._sslobj.read(len, buffer)
socket.timeout: The read operation timed out

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/pip/basecommand.py", line 215, in main
    status = self.run(options, args)
  File "/usr/lib/python3/dist-packages/pip/commands/install.py", line 342, in run
    requirement_set.prepare_files(finder)
  File "/usr/lib/python3/dist-packages/pip/req/req_set.py", line 380, in prepare_files
    ignore_dependencies=self.ignore_dependencies))
  File "/usr/lib/python3/dist-packages/pip/req/req_set.py", line 620, in _prepare_file
    session=self.session, hashes=hashes)
  File "/usr/lib/python3/dist-packages/pip/download.py", line 821, in unpack_url
    hashes=hashes
  File "/usr/lib/python3/dist-packages/pip/download.py", line 659, in unpack_http_url
    hashes)
  File "/usr/lib/python3/dist-packages/pip/download.py", line 882, in _download_http_url
    _download_url(resp, link, content_file, hashes)
  File "/usr/lib/python3/dist-packages/pip/download.py", line 603, in _download_url
    hashes.check_against_chunks(downloaded_chunks)
  File "/usr/lib/python3/dist-packages/pip/utils/hashes.py", line 46, in check_against_chunks
    for chunk in chunks:
  File "/usr/lib/python3/dist-packages/pip/download.py", line 571, in written_chunks
    for chunk in chunks:
  File "/usr/lib/python3/dist-packages/pip/utils/ui.py", line 139, in iter
    for x in it:
  File "/usr/lib/python3/dist-packages/pip/download.py", line 560, in resp_read
    decode_content=False):
  File "/usr/share/python-wheels/urllib3-1.22-py2.py3-none-any.whl/urllib3/response.py", line 436, in stream
    data = self.read(amt=amt, decode_content=decode_content)
  File "/usr/share/python-wheels/urllib3-1.22-py2.py3-none-any.whl/urllib3/response.py", line 401, in read
    raise IncompleteRead(self._fp_bytes_read, self.length_remaining)
  File "/usr/lib/python3.6/contextlib.py", line 99, in __exit__
    self.gen.throw(type, value, traceback)
  File "/usr/share/python-wheels/urllib3-1.22-py2.py3-none-any.whl/urllib3/response.py", line 307, in _error_catcher
    raise ReadTimeoutError(self._pool, None, 'Read timed out.')
urllib3.exceptions.ReadTimeoutError: HTTPSConnectionPool(host='files.pythonhosted.org', port=443): Read timed out.