[
  null,
  {
    "slot": 430000123,
    "confirmations": null,
    "status": {"Ok": null},
    "err": null,
    "confirmationStatus": "finalized"
  },
  {
    "slot": 430000120,
    "confirmations": 3,
    "status": {"Err": {"InstructionError": [0, "Custom"]}},
    "err": {"InstructionError": [0, "Custom"]},
    "confirmationStatus": "confirmed"
  }
]