code: func newRandomColor() color.RGBA {
  	return color.RGBA{
  		R: uint8(rand.Intn(256)),
  		G: uint8(rand.Intn(256)),
  		B: uint8(rand.Intn(256)),
  		A: 0xff,
  	}
  }
docs: // newRandomColor creates a new RGBA color where each channel (except alpha)
  // is randomly generated.