How to actually publish your package to PyPI

Follow this URL to upload your package to test.pypi first:

https://packaging.python.org/tutorials/packaging-projects/#uploading-the-distribution-archives
python3 setup.py sdist bdist_wheel
twine upload --repository-url https://test.pypi.org/legacy/ dist/*
Then try installing it in a new virtualenv:
python3 -m pip install --index-url https://test.pypi.org/simple/ sng
Although I had to use pip3 install --extra-index-url https://test.pypi.org/simple sng, so --extra-index-url instead of index-url because (I think) the PyYAML package was broken on test.pypi (but not on the actual pypi).
If it works, you can proceed to the actual upload:

Increase the version number in __init__.py
Go into doc/ and make html and make latexpdf
Git stuff:
- git commit
- git push origin master
- git tag v0.4 (i.e. a new version)
- git push origin v0.4 (this auto-creates a new release)
Build the new docs at readthedocs
Empty your dist/ directory (not said in the tutorial, but just for good measure).
python3 setup.py sdist bdist_wheel
twine upload dist/*

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