fairseq: Cannot install fairseq==0.10.2 with python 3.9

I don’t seem to be able to install fairseq==0.10.2 with python 3.9 on macOS 11.3

$ pip install fairseq==0.10.2
Collecting fairseq==0.10.2
  Using cached fairseq-0.10.2.tar.gz (938 kB)
  Installing build dependencies ... done
  Getting requirements to build wheel ... error
  ERROR: Command errored out with exit status 1:
   command: /Users/louismartin/miniconda3/envs/dev3.9/bin/python /Users/louismartin/miniconda3/envs/dev3.9/lib/python3.9/site-packages/pip/_vendor/pep517/_in_process.py get_requires_for_build_wheel /var/folders/_4/yxn93yzn14g0_0k2rmctcc1x8lvpn4/T/tmpok_9kdi5
       cwd: /private/var/folders/_4/yxn93yzn14g0_0k2rmctcc1x8lvpn4/T/pip-install-c4qbk_3i/fairseq_751efca8a5d547ada5c29fe71ec11ded
  Complete output (31 lines):
  Traceback (most recent call last):
    File "setup.py", line 214, in <module>
      do_setup(package_data)
    File "setup.py", line 136, in do_setup
      setup(
    File "/private/var/folders/_4/yxn93yzn14g0_0k2rmctcc1x8lvpn4/T/pip-build-env-gi7j5w4c/overlay/lib/python3.9/site-packages/setuptools/__init__.py", line 152, in setup
      _install_setup_requires(attrs)
    File "/private/var/folders/_4/yxn93yzn14g0_0k2rmctcc1x8lvpn4/T/pip-build-env-gi7j5w4c/overlay/lib/python3.9/site-packages/setuptools/__init__.py", line 147, in _install_setup_requires
      dist.fetch_build_eggs(dist.setup_requires)
    File "/private/var/folders/_4/yxn93yzn14g0_0k2rmctcc1x8lvpn4/T/pip-build-env-gi7j5w4c/overlay/lib/python3.9/site-packages/setuptools/build_meta.py", line 60, in fetch_build_eggs
      raise SetupRequirementsError(specifier_list)
  setuptools.build_meta.SetupRequirementsError: ['cython', 'numpy', 'setuptools>=18.0']

  During handling of the above exception, another exception occurred:

  Traceback (most recent call last):
    File "/Users/louismartin/miniconda3/envs/dev3.9/lib/python3.9/site-packages/pip/_vendor/pep517/_in_process.py", line 280, in <module>
      main()
    File "/Users/louismartin/miniconda3/envs/dev3.9/lib/python3.9/site-packages/pip/_vendor/pep517/_in_process.py", line 263, in main
      json_out['return_val'] = hook(**hook_input['kwargs'])
    File "/Users/louismartin/miniconda3/envs/dev3.9/lib/python3.9/site-packages/pip/_vendor/pep517/_in_process.py", line 114, in get_requires_for_build_wheel
      return hook(config_settings)
    File "/private/var/folders/_4/yxn93yzn14g0_0k2rmctcc1x8lvpn4/T/pip-build-env-gi7j5w4c/overlay/lib/python3.9/site-packages/setuptools/build_meta.py", line 154, in get_requires_for_build_wheel
      return self._get_build_requires(
    File "/private/var/folders/_4/yxn93yzn14g0_0k2rmctcc1x8lvpn4/T/pip-build-env-gi7j5w4c/overlay/lib/python3.9/site-packages/setuptools/build_meta.py", line 135, in _get_build_requires
      self.run_setup()
    File "/private/var/folders/_4/yxn93yzn14g0_0k2rmctcc1x8lvpn4/T/pip-build-env-gi7j5w4c/overlay/lib/python3.9/site-packages/setuptools/build_meta.py", line 150, in run_setup
      exec(compile(code, __file__, 'exec'), locals())
    File "setup.py", line 217, in <module>
      os.unlink(fairseq_examples)
  PermissionError: [Errno 1] Operation not permitted: 'fairseq/examples'
  ----------------------------------------
WARNING: Discarding https://files.pythonhosted.org/packages/02/59/1f466d82d64482e2809a167e0067979c23057b3752e668537d5ff24453c9/fairseq-0.10.2.tar.gz#sha256=45b90d8ccc3f5a4623a523fe2d0465f54413d03fd1ec9a9d7af0461148ca1a68 (from https://pypi.org/simple/fairseq/). Command errored out with exit status 1: /Users/louismartin/miniconda3/envs/dev3.9/bin/python /Users/louismartin/miniconda3/envs/dev3.9/lib/python3.9/site-packages/pip/_vendor/pep517/_in_process.py get_requires_for_build_wheel /var/folders/_4/yxn93yzn14g0_0k2rmctcc1x8lvpn4/T/tmpok_9kdi5 Check the logs for full command output.
ERROR: Could not find a version that satisfies the requirement fairseq==0.10.2
ERROR: No matching distribution found for fairseq==0.10.2

Seems to be due to this line