@type t() :: %ExOanda.Response.CancelOrder{
  last_transaction_id: String.t() | nil,
  order_cancel_reject_transaction:
    ExOanda.OrderCancelRejectTransaction.t() | nil,
  order_cancel_transaction: ExOanda.OrderCancelTransaction.t() | nil,
  related_transaction_ids: [String.t()] | nil
}