Build a command-line backup/restore tool at /app/backup.py that creates and verifies timestamped directory…

Build a command-line backup/restore tool at /app/backup.py that creates and verifies timestamped directory…: a task in TermGrade Environments: 1,004 executable Linux tasks (Harbor dataset). Tool interface: python3 /app/backup.py <command <source dir <storage dir options

The task

**Tool interface:** ``` python3 /app/backup.py <command> <source_dir> <storage_dir> [options] ```

Part of ai-and/termgrade-environments.