{
  "chord_rulesets": 
  [
      {
        "scale_cardinality": 7,
        "rules" : [
          [0,2,4],   [0,2,4,6],  [0,2,4,6,8], [0,1,2,3,4]
        ]
      },
      {
        "scale_cardinality": 12,
        "rules" : [
          [0, 4, 7, 11],    [0, 3, 7, 10]
        ]
      },
      {
        "scale_cardinality": 5,
        "rules" : [
          [0,2,3],  
          [0,2,4],  
          [0,2,4,6]
        ]
      }
  ]
}