No wheel on PyPI

I’m experimenting with cross-platform creation of PEX files. One of my dependencies is Gooey which has colored as its dependency. When doing cross-platform builds, pex seems to respect only binary distributions, therefore it fails (only source is uploaded for colored). To be strict, pex delegates the relevant task to pip and the issue can be reproduced by running pip download colored --platform win_amd64-cp-38-cp38. We then get the following error:

ERROR: When restricting platform and interpreter constraints using --python-version, --platform, --abi, or --implementation, either --no-deps must be set, or --only-binary=:all: must be set and --no-binary must not be set (or must be set to :none:).

When we invoke pip download colored --platform win_amd64-cp-38-cp38 --only-binary :all:, the error is:

ERROR: Could not find a version that satisfies the requirement colored (from versions: none) ERROR: No matching distribution found for colored

Can a wheel be published to PyPI? Since this is a pure Python package, one file will suit all platforms.