What is brew cleanup?

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Tags

1. #removing
2. #clearing
3. #cleanup
4. #clean
5. #removed
6. #downloads
7. #older
8. #remove
9. #actually
10. #versions
11. #download
12. #cache
13. #installed
14. #formulae
15. #command
16. #cellar
17. #anything
18. #homebrew
19. #upgrade