Release checklist for maintainers

Note

For demonstration’s sake, we assume that the next version is $VERSION and the package name is $PACKAGE.

Ensure tests pass locally and on CI:
```
pytest
```
Update version in $PACKAGE/_version.py
Compile changelog from news fragments and verify the output, for example:
```
towncrier build --version $VERSION --draft
```
Apply the changelog to CHANGES.rst and edit the links as required:
```
towncrier build --version $VERSION
```
Compile documentation:
```
cd docs/
make html
```
Commit changes and tag a release:
```
hg commit
hg tag $VERSION
```

Prepare source distribution package and wheel:

make clean
python setup.py sdist bdist_wheel

Verify the package with twine:
```
twine check dist/*
```

Upload to TestPyPI and verify:

twine upload --repository testpypi dist/*
cd /tmp
python -m venv testpypi
source testpypi/bin/activate
pip install \
    --index-url https://test.pypi.org/simple \
    --extra-index-url https://pypi.org/simple \
    $PACKAGE

Upload to PyPI:
```
twine upload dist/*
```