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* Drop support for Django < 2.2
* Drop support for Python < 3.7
* Add support for Django 3.1, 3.2, and 4.0
* Add support for Python 3.8, 3.9, and 3.10
* Replace Travis CI with GitHub Actions
* Replace Setuptools with Poetry
* Remove support for universal wheels
* Fix deprecation warning for `ugettext_lazy()`
* Fix deprecation warning for `default_app_config`
* Fix deprecation warning for `Signal.providing_args`
* Remove deprecated `YuglifyCssFilter` and `YuglifyJsFilter` compression filters
* Replace `django.conf.urls.url()` with `django.urls.path()`
* Remove obsolete encoding magic comment
* Remove obsolete unicode string prefix
* Remove obsolete inheritance from `object`
* Make use of f-strings in place of `str.format()` and `%`-formatting