@type t() :: %Stripe.Params.PlanCreateParams{
  active: boolean() | nil,
  amount: integer() | nil,
  amount_decimal: String.t() | nil,
  billing_scheme: String.t() | nil,
  currency: String.t(),
  expand: [String.t()] | nil,
  id: String.t() | nil,
  interval: String.t(),
  interval_count: integer() | nil,
  metadata: map() | nil,
  meter: String.t() | nil,
  nickname: String.t() | nil,
  product: map() | nil,
  tiers: [Stripe.Params.PlanCreateParams.Tiers.t()] | nil,
  tiers_mode: String.t() | nil,
  transform_usage: Stripe.Params.PlanCreateParams.TransformUsage.t() | nil,
  trial_period_days: integer() | nil,
  usage_type: String.t() | nil
}