#sofa_bed__convertible  a sofa that can be converted into a bed
  supertype:  #sofa__couch__lounge  an upholstered seat for more than one person
  subtype:  #davenport  a large sofa usually convertible into a bed
     subtype:  #chesterfield.davenport  an overstuffed davenport with upright armrests
  subtype:  #studio_couch__day_bed__daybed  convertible consisting of an upholstered couch that that can be converted into a double bed

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