KeyError: 'ctranslate2' on installation attempt

[bruceleerabbit]

Installation as a user on a shell account service was attempted by running pip install --verbose argostranslate. The output included a very long list of skipped installations:

…
Skipping link: none of the wheel's tags match: cp310-cp310-win_amd64: https://files.pythonhosted.org/packages/b7/ea/9172bb485a6f4f26d35f9e3bad159436e19582ffebf2dabe9aa5a5fd6a91/ctranslate2-4.3.0-cp310-cp310-win_amd64.whl#sha256=799614577f5646a3a5d9b4ef99730fe4f91ec759936465a81bf02182ae827650 (from https://pypi.org/simple/ctranslate2/) (requires-python:>=3.8)
…

Many of those lead up to:

…
Given no hashes to check 3 links for project 'ctranslate2': discarding no candidates
Collecting ctranslate2<5,>=4.0
  Created temporary directory: /tmp/pip-unpack-2gx25dj9
  Getting credentials from keyring for files.pythonhosted.org
  Looking up "https://files.pythonhosted.org/packages/54/5a/004d872da49aa4a6f1fd23220f9c50c253b8996d2d8767ed368c58001a04/ctranslate2-4.2.1-
cp39-cp39-manylinux_2_17_x86_64.manylinux2014_x86_64.whl" in the cache
  No cache entry available
  https://files.pythonhosted.org:443 "GET /packages/54/5a/004d872da49aa4a6f1fd23220f9c50c253b8996d2d8767ed368c58001a04/ctranslate2-4.2.1-cp
39-cp39-manylinux_2_17_x86_64.manylinux2014_x86_64.whl HTTP/1.1" 200 179330893
  Downloading ctranslate2-4.2.1-cp39-cp39-manylinux_2_17_x86_64.manylinux2014_x86_64.whl (179.3 MB)
     |████████████████████████████████| 179.3 MB 264 kB/s eta 0:00:01  Ignoring unknown cache-control directive: immutable
  Updating cache with response from "https://files.pythonhosted.org/packages/54/5a/004d872da49aa4a6f1fd23220f9c50c253b8996d2d8767ed368c5800
1a04/ctranslate2-4.2.1-cp39-cp39-manylinux_2_17_x86_64.manylinux2014_x86_64.whl"
  Caching due to etag
ERROR: Exception:
Traceback (most recent call last):
  File "/usr/share/python-wheels/resolvelib-0.5.4-py2.py3-none-any.whl/resolvelib/resolvers.py", line 171, in _merge_into_criterion
    crit = self.state.criteria[name]
KeyError: 'ctranslate2'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/pip/_internal/cli/base_command.py", line 223, in _main
    status = self.run(options, args)
  File "/usr/lib/python3/dist-packages/pip/_internal/cli/req_command.py", line 180, in wrapper
    return func(self, options, args)
  File "/usr/lib/python3/dist-packages/pip/_internal/commands/install.py", line 346, in run
    requirement_set = resolver.resolve(
  File "/usr/lib/python3/dist-packages/pip/_internal/resolution/resolvelib/resolver.py", line 122, in resolve
    self._result = resolver.resolve(
  File "/usr/share/python-wheels/resolvelib-0.5.4-py2.py3-none-any.whl/resolvelib/resolvers.py", line 453, in resolve
    state = resolution.resolve(requirements, max_rounds=max_rounds)
  File "/usr/share/python-wheels/resolvelib-0.5.4-py2.py3-none-any.whl/resolvelib/resolvers.py", line 347, in resolve
    failure_causes = self._attempt_to_pin_criterion(name, criterion)
  File "/usr/share/python-wheels/resolvelib-0.5.4-py2.py3-none-any.whl/resolvelib/resolvers.py", line 207, in _attempt_to_pin_criterion
    criteria = self._get_criteria_to_update(candidate)
  File "/usr/share/python-wheels/resolvelib-0.5.4-py2.py3-none-any.whl/resolvelib/resolvers.py", line 199, in _get_criteria_to_update
    name, crit = self._merge_into_criterion(r, parent=candidate)
  File "/usr/share/python-wheels/resolvelib-0.5.4-py2.py3-none-any.whl/resolvelib/resolvers.py", line 173, in _merge_into_criterion
    crit = Criterion.from_requirement(self._p, requirement, parent)
  File "/usr/share/python-wheels/resolvelib-0.5.4-py2.py3-none-any.whl/resolvelib/resolvers.py", line 82, in from_requirement
    if not cands:
  File "/usr/share/python-wheels/resolvelib-0.5.4-py2.py3-none-any.whl/resolvelib/structs.py", line 124, in __bool__
    return bool(self._sequence)
  File "/usr/lib/python3/dist-packages/pip/_internal/resolution/resolvelib/found_candidates.py", line 99, in __bool__
    return any(self)
  File "/usr/lib/python3/dist-packages/pip/_internal/resolution/resolvelib/factory.py", line 239, in iter_index_candidates
    candidate = self._make_candidate_from_link(
  File "/usr/lib/python3/dist-packages/pip/_internal/resolution/resolvelib/factory.py", line 167, in _make_candidate_from_link
    self._link_candidate_cache[link] = LinkCandidate(
…[snip]…
  File "/usr/share/python-wheels/CacheControl-0.12.6-py2.py3-none-any.whl/cachecontrol/controller.py", line 309, in cache_response
    cache_url, self.serializer.dumps(request, response, body=body)
  File "/usr/share/python-wheels/CacheControl-0.12.6-py2.py3-none-any.whl/cachecontrol/serialize.py", line 72, in dumps
    return b",".join([b"cc=4", msgpack.dumps(data, use_bin_type=True)])
MemoryError

All the skipped files output says “requires-python:>=3.8”. The shell service has many versions installed, but 3.9 seems to be the default IIUC:

$ python<tab>
python2           python3           python3.7         python3.9         python3-config
python2.7         python3.5         python3.7m        python3.9-config
$ pip --version
pip 20.3.4 from /usr/lib/python3/dist-packages/pip (python 3.9)

It’s ½ tempting to try python3.9 -m pip install argostranslate, but it looks like pip is automatically selecting python 3.9.