Update Python from 3.8 to 3.9

[nickspaargaren]

What

• Updates the project used Python version from 3.8 to 3.9
• Why? 3.8 has become unsupported, see: https://devguide.python.org/versions/#supported-versions

How to test

• Follow the "Installing the project" instructions.
• Make sure the projects runs on Python 3.9
• Check out the Python 3.9 deprecated section for breaking changes
• All GitHub Actions (pipelines) should pass

---

📚 Documentation preview 📚: https://writethedocs-www--2271.org.readthedocs.build/

[ericholscher]

Thanks for your work here!

If we're doing this work, I wonder if it makes sense to upgrade to 3.10 or 3.11, so we're a bit closer to the latest version? Might cause more cascading dependency upgrades though.

[plaindocs]

I took a quick look at the two broken links, and they seem pretty irrelevant to this PR, which does make me wonder why they aren't failing the main build:

 For the Links > Internal check, the following failures were found:

* At docs/_build/html/blog/archive/tag/index.html:75:

  internally linking to ../../../../, which does not exist

* At docs/_build/html/blog/archive/tag/index.html:140:

  internally linking to ../../../../, which does not exist

[nickspaargaren]

I took a quick look at the two broken links, and they seem pretty irrelevant to this PR, which does make me wonder why they aren't failing the main build:

 For the Links > Internal check, the following failures were found:



* At docs/_build/html/blog/archive/tag/index.html:75:



  internally linking to ../../../../, which does not exist



* At docs/_build/html/blog/archive/tag/index.html:140:



  internally linking to ../../../../, which does not exist

Yeah i'm seeing this as well. I was trying different pip modules/package versions to tackle this. No solution yet.. Maybe there are indeed wrong links?

[plaindocs]

Yeah it's probably a difference in behaviour from the HTML output?

This ugliness is L75:

          <div class="breadcrumbs">
            
            
              <a href="../../../../">Home</a> &raquo;
                
            
          </div>

The href here is L140:

<p class="logo">
  <a href="../../../../">
    <img class="logo" src="../../../../_static/sticker-wtd-colors.png" alt="Logo" />
    
  </a>
</p>

Could track down where it's generated, and if there isn't an obvious fix, just ignore it? :-p

https://github.com/gjtorikian/html-proofer?tab=readme-ov-file#ignoring-content

[plaindocs]

If we want to make this pass I'm happy to exclude docs/_build/html/blog/archive/tag/index.html manually in the htmlproofer call in CI and add an issue to look into it at another date.

[nickspaargaren]

If we want to make this pass I'm happy to exclude docs/_build/html/blog/archive/tag/index.html manually in the htmlproofer call in CI and add an issue to look into it at another date.

Thanks for understanding! Let me look into it one more time, maybe i can come up with a fix. Otherwise let's ignore it.

[plaindocs]

I wonder if diffing the ablog source between the versions would help? I don't think we've got custom ablog templates in our repo.