-Test if the file is read-only in rm.py;
-ask the user if they wants to delete it.
+PyPy.
-Add option -f for rm.py.
-
-
-Add option -s for cmp.py.
+Add option -s --quiet --silent for cmp.py.
Extend remove-old-files.py: add option -v/--verbose to report every removed file.