@type t() :: %MBTA.Model.ScheduleResourceRelationships{
  prediction: MBTA.Model.ScheduleResourceRelationshipsPrediction.t() | nil,
  route: MBTA.Model.ScheduleResourceRelationshipsRoute.t() | nil,
  stop: MBTA.Model.ScheduleResourceRelationshipsStop.t() | nil,
  trip: MBTA.Model.ScheduleResourceRelationshipsTrip.t() | nil
}