code: def test_rgb_to_hsl_part_16():
      """Test rgb to hsl color function"""
      # assert rgb_to_hsl(0, 0, 0) == (180, 100, 0)
      assert rgb_to_hsl(0, 51, 51) == (180, 100, 10)
      assert rgb_to_hsl(0, 102, 102) == (180, 100, 20)
      assert rgb_to_hsl(0, 153, 153) == (180, 100, 30)
      assert rgb_to_hsl(0, 204, 204) == (180, 100, 40)
      assert rgb_to_hsl(0, 255, 255) == (180, 100, 50)
      assert rgb_to_hsl(51, 255, 255) == (180, 100, 60)
      assert rgb_to_hsl(102, 255, 255) == (180, 100, 70)
      assert rgb_to_hsl(153, 255, 255) == (180, 100, 80)
      assert rgb_to_hsl(204, 255, 255) == (180, 100, 90)
  
imports: from __future__ import division
  from pygal.colors import darken, desaturate, hsl_to_rgb, lighten, parse_color, rgb_to_hsl, rotate, saturate, unparse_color
label_desc: Use image node_id 41 for calling a global function with example usage: test_rgb_to_hsl_part_16() without return types