ensure_python deprecated in python 3.10

[jonringer]

Description

ensure_python deprecated in python 3.10, will kill sdist installation.

Reproduce

1. Install python 3.10, pip, setuptools
2. Run:

pip install --user https://files.pythonhosted.org/packages/27/f1/0d3a09c0069467ed9636faf3a9b5b758378216bb891066a0bc24799681e3/jupyterlab_widgets-1.0.2.tar.gz

Expected behavior

Doesn't fail

Context

relevant logs:

    File "setup.py", line 18, in <module>
      ensure_python(">=3.6")
    File "/run/user/1000/pip-build-env-s322v3pd/overlay/lib/python3.10/site-packages/jupyter_packaging/setupbase.py", line 103, in ensure_python
      raise ValueError('Python version %s unsupported' % part)
  ValueError: Python version 3.10 unsupported

Full logs:

$ pip install --user https://files.pythonhosted.org/packages/27/f1/0d3a09c0069467ed9636faf3a9b5b758378216bb891066a0bc24799681e3/jupyterlab_widgets-1.0.2.tar.gz
Collecting https://files.pythonhosted.org/packages/27/f1/0d3a09c0069467ed9636faf3a9b5b758378216bb891066a0bc24799681e3/jupyterlab_widgets-1.0.2.tar.gz
  Using cached jupyterlab_widgets-1.0.2.tar.gz (118 kB)
  Installing build dependencies ... done
  Getting requirements to build wheel ... error
  ERROR: Command errored out with exit status 1:
   command: /nix/store/b798fp24zf2fdafmyyc4sxfr48ly5yy9-python3-3.10.1/bin/python3.10 /nix/store/37l3w8cibfijh8if4iy25ra37zi5pdds-python3.10-pip-21.3.1/lib/python3.10/site-packages/pip/_vendor/pep517/in_process/_in_process.py get_requires_for_build_wheel /run/user/1000/tmp1puyfj05
       cwd: /run/user/1000/pip-req-build-17ejtea5
  Complete output (18 lines):
  Traceback (most recent call last):
    File "/nix/store/37l3w8cibfijh8if4iy25ra37zi5pdds-python3.10-pip-21.3.1/lib/python3.10/site-packages/pip/_vendor/pep517/in_process/_in_process.py", line 363, in <module>
      main()
    File "/nix/store/37l3w8cibfijh8if4iy25ra37zi5pdds-python3.10-pip-21.3.1/lib/python3.10/site-packages/pip/_vendor/pep517/in_process/_in_process.py", line 345, in main
      json_out['return_val'] = hook(**hook_input['kwargs'])
    File "/nix/store/37l3w8cibfijh8if4iy25ra37zi5pdds-python3.10-pip-21.3.1/lib/python3.10/site-packages/pip/_vendor/pep517/in_process/_in_process.py", line 130, in get_requires_for_build_wheel
      return hook(config_settings)
    File "/run/user/1000/pip-build-env-s322v3pd/overlay/lib/python3.10/site-packages/setuptools/build_meta.py", line 162, in get_requires_for_build_wheel
      return self._get_build_requires(
    File "/run/user/1000/pip-build-env-s322v3pd/overlay/lib/python3.10/site-packages/setuptools/build_meta.py", line 143, in _get_build_requires
      self.run_setup()
    File "/run/user/1000/pip-build-env-s322v3pd/overlay/lib/python3.10/site-packages/setuptools/build_meta.py", line 158, in run_setup
      exec(compile(code, __file__, 'exec'), locals())
    File "setup.py", line 18, in <module>
      ensure_python(">=3.6")
    File "/run/user/1000/pip-build-env-s322v3pd/overlay/lib/python3.10/site-packages/jupyter_packaging/setupbase.py", line 103, in ensure_python
      raise ValueError('Python version %s unsupported' % part)
  ValueError: Python version 3.10 unsupported
  ----------------------------------------
WARNING: Discarding https://files.pythonhosted.org/packages/27/f1/0d3a09c0069467ed9636faf3a9b5b758378216bb891066a0bc24799681e3/jupyterlab_widgets-1.0.2.tar.gz. Command errored out with exit status 1: /nix/store/b798fp24zf2fdafmyyc4sxfr48ly5yy9-python3-3.10.1/bin/python3.10 /nix/store/37l3w8cibfijh8if4iy25ra37zi5pdds-python3.10-pip-21.3.1/lib/python3.10/site-packages/pip/_vendor/pep517/in_process/_in_process.py get_requires_for_build_wheel /run/user/1000/tmp1puyfj05 Check the logs for full command output.
ERROR: Command errored out with exit status 1: /nix/store/b798fp24zf2fdafmyyc4sxfr48ly5yy9-python3-3.10.1/bin/python3.10 /nix/store/37l3w8cibfijh8if4iy25ra37zi5pdds-python3.10-pip-21.3.1/lib/python3.10/site-packages/pip/_vendor/pep517/in_process/_in_process.py get_requires_for_build_wheel /run/user/1000/tmp1puyfj05 Check the logs for full command output.
WARNING: You are using pip version 21.3.1; however, version 22.0.2 is available.
You should consider upgrading via the '/nix/store/b798fp24zf2fdafmyyc4sxfr48ly5yy9-python3-3.10.1/bin/python3.10 -m pip install --upgrade pip' command.

don't worry about the /nix/store paths.

[jasongrout]

Thanks. We may need to just bump our requirement for jupyter_packaging to the latest version.

[jasongrout]

Actually, the jupyter_packaging code says to just use python_requires instead: https://github.com/jupyter/jupyter-packaging/blob/fe87c6ae46df9d13c363111aa4fbfb3c25418843/jupyter_packaging/setupbase.py#L462-L463

Use setuptools python_requires instead

[jasongrout]

ensure_python is not used on master, only on the 7.x series, so #3368 just takes care of it on the 7.x branch.

[jasongrout]

FIxed in #3368

[jonringer]

Thanks :)

[jasongrout]

We plan to release later this week or next week.