new_contents: import uos, nrf
  
  try:
      from uos import VfsLfs1
  
      uos.VfsLfs1.mkfs(nrf.Flash())
  except ImportError:
      try:
          from uos import VfsLfs2
  
          uos.VfsLfs2.mkfs(nrf.Flash())
      except ImportError:
          try:
              from uos import VfsFat
  
              uos.VfsFat.mkfs(nrf.Flash())
          except ImportError:
              pass
          except OSError as e:
              if e.args[0] == 5:  # I/O Error
                  flashbdev_size = (nrf.Flash.ioctl(4, 0) * nrf.Flash.ioctl(5, 0)) // 1024
                  print()
                  print("Is `FS_SIZE=%iK` enough for FAT filesystem?" % flashbdev_size)
  
subject: Add file system formatting script.