gh-143674: Document F/D complex format characters in struct module

[moneebullah25]

Fixes#143674

Changes

• Added documentation for F (complex from two floats) and D (complex from two doubles) format characters to the struct module docstring

Rationale

These format characters are implemented in the struct module (lines 858-859, 1189-1190, 1504-1505 in Modules/_struct.c) but were missing from the module's docstring documentation. Users consulting the docstring with help(struct) would not know these options exist.

Testing

• Verified that F and D format characters are implemented in the code
• Confirmed the docstring change follows the existing format and style
• The change is minimal and only adds missing documentation

Checklist

• Minimal change - only added missing documentation
• Followed existing docstring format and style
• Commit message follows CPython guidelines

• Issue: Struct module docstring lacks format characters for complex types (F/D) #143674

[skirpichev]

Are you using generative AI for this pr?

[moneebullah25]

Are you using generative AI for this pr?

Yep I use it for commit message and comment

[hugovk]

Reported @quanghuynh10111-lab to GitHub.

[miss-islington-app]

Thanks @moneebullah25 for the PR, and @vstinner for merging it 🌮🎉.. I'm working now to backport this PR to: 3.14.
🐍🍒⛏🤖

[bedevere-app]

GH-143918 is a backport of this pull request to the 3.14 branch.

[vstinner]

Merged, thank you.

[bedevere-bot]

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot ARM64 macOS 3.x (tier-2) has failed when building commit 3e93225.

What do you need to do:

1. Don't panic.
2. Check the buildbot page in the devguide if you don't know what the buildbots are or how they work.
3. Go to the page of the buildbot that failed (https://buildbot.python.org/#/builders/725/builds/12571) and take a look at the build logs.
4. Check if the failure is related to this commit (3e93225) or if it is a false positive.
5. If the failure is related to this commit, please, reflect that on the issue and make a new Pull Request with a fix.

You can take a look at the buildbot page here:

https://buildbot.python.org/#/builders/725/builds/12571

Failed tests:

• test_urllib2net

Summary of the results of the build (if available):

==

Click to see traceback logs

remote: Enumerating objects: 4, done. remote: Counting objects: 25% (1/4) remote: Counting objects: 50% (2/4) remote: Counting objects: 75% (3/4) remote: Counting objects: 100% (4/4) remote: Counting objects: 100% (4/4), done. remote: Compressing objects: 25% (1/4) remote: Compressing objects: 50% (2/4) remote: Compressing objects: 75% (3/4) remote: Compressing objects: 100% (4/4) remote: Compressing objects: 100% (4/4), done. remote: Total 4 (delta 0), reused 3 (delta 0), pack-reused 0 (from 0)  From https://github.com/python/cpython * branch main -> FETCH_HEAD Note: switching to '3e932257980be8907698c378c23026e262ba066c'. You are in 'detached HEAD' state. You can look around, make experimental changes and commit them, and you can discard any commits you make in this state without impacting any branches by switching back to a branch. If you want to create a new branch to retain commits you create, you may do so (now or later) by using -c with the switch command. Example: git switch -c <new-branch-name> Or undo this operation with: git switch - Turn off this advice by setting config variable advice.detachedHead to false HEAD is now at 3e932257980 gh-143674: Document F/D complex format characters in struct module (#143675) Switched to and reset branch 'main' make: *** [buildbottest] Error 2