function orangeFeetMixin<T extends DuckConstructor>(Duck: T) {
  return class orangeFeetDuck extends Duck {
    hasOrangeFeet(): boolean {
      return true
    }

    getFeatherColours(): string {
      return 'orange'
    }
  };
}
	function orangeFeetMixin<T extends DuckConstructor>(Duck: T) {
	return class orangeFeetDuck extends Duck {
	hasOrangeFeet(): boolean {
	return true
	}

	getFeatherColours(): string {
	return 'orange'
	}
	};
	}