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* [BREAKING] drop support for Django 3.0
* add support for Python 3.9 and 3.10
* add support for Django 3.2
* starting this version, migrations for UIDField include `prefix` and `chars`
arguments, specific for the field type. They are required for proper field
usage in data migrations. As a side effect of this update,
the `makemigrations` command will generate AlterField migrations for all
existing UID fields in the project after upgrading from earlier versions.
These migrations won't perform any SQL queries, though.