Make Download page translatable

[rffontenelle]

Documentation

The Python docs' Download page (https://docs.python.org/3/download.html) is not currently available for translation, hence differentiating from other pages that received the translations effort of the language teams.

Strings should be marked for translation, so the file's strings are properly extracted into translation files.

To reproduce:

1. make -C Doc venv gettext # from local CPython checkout
2. search (unsuccessfully) strings in the .pot files generate in 'Doc/build/gettext/' directory for the translation strings that should be extracted from 'Doc/tools/templates/download.html' file (e.g. grep -R 'These archives contain all the content in the documentation.' Doc/build/gettext)

Linked PRs

• gh-122384: Mark strings from Download page for translation #122385
• [3.13] gh-122384: Mark strings from Download page for translation (GH-122385) #122553
• [3.12] gh-122384: Mark strings from Download page for translation (GH-122385) #122554

[Wulian233]

A similar problem appears in the footer of every page. I tried to search for keywords, but couldn't find anything relevant.

[hugovk]

Some of that comes from the theme, for example: https://github.com/python/python-docs-theme/blob/f1ba0f8c86f859be2a800fae8af00ec4a7e48039/python_docs_theme/layout.html#L147

[Wulian233]

looks there has {% trans %}{% endtrans %}, and I've switched a lot of different languages, but there's no actual translation 🤔🤔❓

[rffontenelle]

python-doc-theme is not being translated. It is a separate repository, and translators only translate the documentation from cpython repository. This should probably change.

[hugovk]

See python/python-docs-theme#194 for localising the theme.