#sleeping_car__sleeper__wagon-lit__wagonlit  a passenger car that has berths for sleeping
  supertype:  passenger_car__passengercar__coach__carriage  a railcar where passengers ride
  part:  drawing_room__drawingroom  a private compartment on a sleeping car with three bunks and a toilet
  part:  roomette  a small private compartment for one on a sleeping car

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