Package issue: Pillow yields ImportError: cannot import name '_imaging'

[rasmuslp]

Package name

pillow

Package version

8.3.2

PyPI URL

https://pypi.org/project/Pillow/

piwheels URL

https://www.piwheels.org/project/pillow/

Python version

• [ ] Python 3.5
• [ ] Python 3.7
• [X] Python 3.9

I am the maintainer

• [ ] Yes

More information

I'm building a Docker image based on python:3.9.6-slim-buster for the platform linux/arm/v6 to run on a Raspberry Pi Zero.

After adding --extra-index-url https://www.piwheels.org/simple to my requirements.txt I now get the following stack trace when trying to start the container:

Traceback (most recent call last):
  File "/usr/local/lib/python3.9/runpy.py", line 197, in _run_module_as_main
    return _run_code(code, main_globals, None,
  File "/usr/local/lib/python3.9/runpy.py", line 87, in _run_code
    exec(code, run_globals)
  File "/usr/src/app/display/__main__.py", line 4, in <module>
    from display.cli import cli
  File "/usr/src/app/display/cli.py", line 10, in <module>
    from display.display import Display
  File "/usr/src/app/display/display.py", line 3, in <module>
    from PIL import Image
  File "/usr/src/app/.venv/lib/python3.9/site-packages/PIL/Image.py", line 114, in <module>
    from . import _imaging as core
ImportError: cannot import name '_imaging' from 'PIL' (/usr/src/app/.venv/lib/python3.9/site-packages/PIL/__init__.py)

However, when I inspect the image there is a file at the path /usr/src/app/.venv/lib/python3.9/site-packages/PIL/_imaging.cpython-39-arm-linux-gnueabihf.so