Problem: Python 3.9 reaches EOL next October, 2025

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Expected behaviour

All Archivematica related components written in Python run only on supported Python versions.

Current behaviour

All the Archivematica related components have Python 3.9 as their default version, but 3.9 reaches its end of life on 2025-10-07.

At that point many dependencies will no longer support 3.9, so we'll have to pin them to outdated versions, which can cause security risks and make future upgrades harder.

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For Artefactual use:

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• All pull requests related to this issue are properly linked
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• A testing plan for this issue has been implemented and passed (testing plan information should be included in the issue body or comments)
• Documentation regarding this issue has been written and merged (if applicable)
• Details about this issue have been added to the release notes (if applicable)