code: def test_rgb_to_hsl_part_6():
      """Test rgb to hsl color function"""
      assert rgb_to_hsl(0, 0, 255) == (240, 100, 50)
      assert rgb_to_hsl(51, 0, 255) == (252, 100, 50)
      assert rgb_to_hsl(102, 0, 255) == (264, 100, 50)
      assert rgb_to_hsl(153, 0, 255) == (276, 100, 50)
      assert rgb_to_hsl(204, 0, 255) == (288, 100, 50)
      assert rgb_to_hsl(255, 0, 255) == (300, 100, 50)
      assert rgb_to_hsl(255, 0, 204) == (312, 100, 50)
      assert rgb_to_hsl(255, 0, 153) == (324, 100, 50)
      assert rgb_to_hsl(255, 0, 102) == (336, 100, 50)
      assert rgb_to_hsl(255, 0, 51) == (348, 100, 50)
  
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 21 for calling a global function with example usage: test_rgb_to_hsl_part_6() without return types