Improve Code Quality

Help me improve this code's quality:

CURRENT CODE:
[Paste your code]

Issues I'm concerned about:
- [Concern 1]
- [Concern 2]

I want improvements in:
- [ ] Readability
- [ ] Maintainability
- [ ] Testability
- [ ] Performance
- [ ] Error handling

Keep the same functionality but make it [cleaner/faster/more robust].

Show me the improved version with comments explaining changes.