The version field is missing from the setup.cfg metadata

[mickours]

There is currently no version field in the setup.cfg [metadata] section which leads to errors in dependencies resolution for custom packaging tools. See nix-community/poetry2nix#123 (comment)

Adding the field fix the problem.

[FFY00]

This is intended behavior, your tooling is not handling this correctly. This project does not want to manually maintain a version field, instead it uses setuptools_scm to handle that automatically.
Your tooling is relying on implementation details of setuptools which are not suposed to be relied upon. I recommend you switch your tooling to use PEP 517.

[mickours]

Ok thanks. Indeed it seems that Poetry does not support PEP 517 for now but the work is in progress python-poetry/poetry#2794.

Closing.