DeprecationWarning upon "import holidays" in version 0.17

The implementation of deprecating the Swaziland calendar contains a bug. Just importing the holidays package is enough to fire the DeprecationWarning.

Steps to reproduce (in bash):

# Setup
python -m venv demo
source demo/bin/activate
pip install --upgrade pip

# Bad version
pip install holidays==0.17

# Expose bug
python -W error::DeprecationWarning -c 'import holidays'

# Workoround
pip uninstall -y holidays
pip install holidays!=0.17
python -W error::DeprecationWarning -c 'import holidays'

# Cleanup
deactivate
rm -rf demo

Expected behavior:

The DeprecationWarning should only fire when the user constructs an instance of the Swaziland or a subclass.

[dr-prodigy]

Unfortunately I could not work on a new release for some days… now it’s online and should be okay. Thx!

[arkid15r]

The suggested fix was implemented in #794 PR yesterday.

Thank you!