transaction fee in BTC, omitted if block undo data is not available
  "vin" : [                          (json array)
    {                                (json object) utxo being spent
      ...,                           Same output as verbosity = 1
      "prevout" : {                  (json object, optional) The previous output, omitted if block undo data is not available
        "generated" : true|false,    (boolean) Coinbase or not
        "height" : n,                (numeric) The height of the prevou