old_contents: try:
      import rc
  except ImportError:
      import vx
  
      # which keybinding do we want
      from keybindings import hopscotch
  
      vx.default_start()
  
new_contents: try:
      import rc
  except ImportError:
      import vx
  
      # which keybinding do we want
      from keybindings import concat
      vx.default_keybindings = concat.load
  
      vx.default_start()
  
subject: Change default keybindings to concat since these are the only ones that work