There's a merged pull request on the void-packages repository

python3-matplotlib: update to 3.8.1.
https://github.com/void-linux/void-packages/pull/47068

Description:
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Also included here a couple of dependencies:
 - python3-cycler: update to 0.12.1.
 - python3-contourpy: update to 1.2.0, adopt.

#### Testing the changes
- I tested the changes in this PR: **briefly**

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