gh-35543: Cleaning set partition

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### 📚 Description

Various details and tweaks in the code and doc of `set_partition.py`

in order to reach full pep8 and better pylint compliance

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URL: #35543
Reported by: Frédéric Chapoton
Reviewer(s): Martin Rubey, Matthias Köppe

Author: Release Manager

build/pkgs/configure/checksums.ini

@@ -1,4 +1,4 @@
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build/pkgs/configure/package-version.txt

@@ -1 +1 @@
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