[SYSTEMDS-3330] Corrections to Generator for f_ functions.

[Baunsgaard]

This commit resolves some inconsistent behavior in the generation
of builtin functions in python generated files.

See #2291 for original PR.

This PR is for merging the original.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 72.26%. Comparing base (7038acf) to head (f00b636).
⚠️ Report is 3 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #2333      +/-   ##
============================================
- Coverage     72.27%   72.26%   -0.02%     
+ Complexity    46677    46671       -6     
============================================
  Files          1501     1501              
  Lines        177023   177023              
  Branches      34791    34791              
============================================
- Hits         127942   127919      -23     
- Misses        39426    39447      +21     
- Partials       9655     9657       +2     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.