@type t() :: %Railsr.Types.Ledger{
  amount_available: non_neg_integer() | nil,
  amount_reserved: non_neg_integer() | nil,
  asset_class: String.t() | nil,
  asset_type: String.t() | nil,
  balance: non_neg_integer() | nil,
  bic: String.t() | nil,
  created_at: String.t() | nil,
  currency: String.t() | nil,
  customer_id: String.t() | nil,
  holder_id: String.t() | nil,
  holder_type: String.t() | nil,
  iban: String.t() | nil,
  ledger_id: String.t() | nil,
  ledger_type: String.t() | nil,
  metadata: map() | nil,
  status: String.t() | nil,
  uk_account_number: String.t() | nil,
  uk_sort_code: String.t() | nil,
  updated_at: String.t() | nil
}