{
  "customers": [
    { 
      "name": "John Smith",
      "age": 23,
      "is_last_bill_paid": true
    },
    { 
      "name": "Alice Martin",
      "age": 34,
      "is_last_bill_paid": false
    },
    { 
      "name": "Joe West",
      "age": 45,
      "is_last_bill_paid": false
    },
    { 
      "name": "Mary Moss",
      "age": 56,
      "is_last_bill_paid": true
    }
  ]
}