code: def clean_all(ctx, dry_run=False):
      
      cleanup_dirs(ctx.clean_all.directories or [], dry_run=dry_run)
      cleanup_dirs(ctx.clean_all.extra_directories or [], dry_run=dry_run)
      cleanup_files(ctx.clean_all.files or [], dry_run=dry_run)
      cleanup_files(ctx.clean_all.extra_files or [], dry_run=dry_run)
      execute_cleanup_tasks(ctx, cleanup_all_tasks, dry_run=dry_run)
      clean(ctx, dry_run=dry_run)
docs: Clean up everything, even the precious stuff.
      NOTE: clean task is executed first.