People have stopped publishing source packages!

[frankier]

It seem that in the rush to use wheels, many people are now no longer publishing source packages. This causes havoc with new versions of Python which will go way back into the past looking for a version with a source package

Here's a couple of examples:

• Source packages not published to PyPI pytorch/vision#2359
• New PyPI packages don't have source code hfst/hfst#462

It would be nice to include in the messaging/tracking that both should be published.

[hugovk]

https://pythonwheels.com/ already says to create both:

…and when you'd normally run python setup.py sdist, run instead python setup.py sdist bdist_wheel

But would you like to create a PR to make the text more explicit?