def scene=(n)
      if n.nil?
        Kernel.raise IndexError, 'scene number out of bounds' unless @images.length.zero?
        @scene = nil
        return @scene
      elsif @images.length.zero?
        Kernel.raise IndexError, 'scene number out of bounds'
      end

      n = Integer(n)
      Kernel.raise IndexError, 'scene number out of bounds' if n < 0 || n > length - 1
      @scene = n
      @scene
    end
def scene=(n)
      if n.nil?
        Kernel.raise IndexError, 'scene number out of bounds' unless @images.length.zero?
        @scene = nil
        return @scene
      elsif @images.length.zero?
        Kernel.raise IndexError, 'scene number out of bounds'
      end

      n = Integer(n)
      Kernel.raise IndexError, 'scene number out of bounds' if n < 0 || n > length - 1
      @scene = n
      @scene
    end
Allow scene to be set to nil