code: def cmy(self):
          
          r, g, b = self.color
          c = 1 - r
          m = 1 - g
          y = 1 - b
  
          return (c, m, y)
docs: CMY: returned in range 0.0 - 1.0
          CMY is subtractive, e.g. black: (1, 1, 1), white (0, 0, 0)