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- Added the license to the source distribution, thanks to Joshua Adelman
- Added Python 3.9 and 3.10 support, this includes fixing Python 3.10 compatibility, thanks to Torge Matthies
- Improved the documentation, thanks to Takahiro Kojima
- Improved the source distribution so that it can be used to build and install wheels, thanks to Janusz Skonieczny
- Added requirements files for easier development, thanks to Greg Eremeev
Backwards incompatible:
- Removed Python 3.5 support