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Merge pull request #42 from deeplook/change-license-to-mit

Switch to MIT license and bump version to 0.7.0

Add mypy to workflow, bump version to 0.6.0

Fix badge

Drop Python 3.8 support

Use Union instead of pipe

Use Optional instead of pipe

Use Optional instead of pipe

Add type annotations

Add missing dash

Change dev status from beta to stable

Add contributor

Ruff format

Refactor CI, merge ruff with existing action