// "override" keyword overrides patrimonial "virtual" ReturnContents method
public override void ReturnContents(Jewels safeContents, Owner owner)
{
stolenJewels = safeContents;
Console.WriteLine("I'm steal the contents of the safe!" + stolenJewels.Sparkle());
}
public void ReceiveContents(Jewels safeContents)
{
returnedContents = safeContents;
Console.WriteLine("Thanks for bringing jewels. " + safeContents.Sparkle());
}