@type t() :: %ExOura.Client.PublicRingConfiguration{
  color: String.t() | nil,
  design: String.t() | nil,
  firmware_version: String.t() | nil,
  hardware_type: String.t() | nil,
  id: String.t(),
  set_up_at: String.t() | nil,
  size: integer() | nil
}