@type reference_item() :: %{key: String.t(), value: term()} | nil

@type result_parameter() :: %{key: String.t(), value: term()}

@type t() :: %Daraja.B2C.Callback.Result{
  conversation_id: String.t() | nil,
  originator_conversation_id: String.t() | nil,
  reference_item: reference_item(),
  result_code: String.t() | integer() | nil,
  result_desc: String.t() | nil,
  result_parameters: [result_parameter()],
  result_parameters_map: %{optional(String.t()) => term()},
  result_type: integer() | nil,
  transaction_id: String.t() | nil
}