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* :code:`-r/--repeat` option for repeating input files
* Constrain :code:`click` version to :code:`<8.1` due to breaking API change; this will be relaxed in a future version
* Constrain :code:`Pillow` version to :code:`<9.0` due to breaking tests; this will be relaxed in a future version
* Drop support for Python 3.6 and 3.7
* Add support for Python 3.9 and 3.10
* Upgrade dependencies
* Migrate from travis-ci.com to GitHub actions