How to implement an inteface to a sealed class?

// CODE BELOW CANNOT BE MODIFIED, TREAT IT AS A 3TH PARTY LIBRARY
    public interface IDoors
    {
        void PullHandle();
    }
    
    class NormalDoors : IDoors
    {
        public void PullHandle()
        {
            Console.WriteLine("Normal doors open");
        }
    }
    
    public static class Doorman
    {
        public static void Open(IDoors doors)
        {
            doors.PullHandle();
        }
    }
    
    public sealed class FancyDoors
    {
        public void PressButton()
        {
            Console.WriteLine("Fancy doors are open");
        }
    }
    
//BELOW YOU CAN ADD CODE TO SOLVE THE PROBLEM

    
    public static class Doors
    {
        public static void Main()
        {
            var myNormalDoors = new NormalDoors();
            var myFancyDoors = new FancyDoors();
    
            // This works, since normal doors implement IDoors
            Doorman.Open(myNormalDoors);
            
            //Doesn't work, because Fancy Doors are sealed and do not                            implement IDoors. How to bypass that problem?
            Doorman.Open(myFancyDoors );
        }
    }
}