code: def test():
      runner = unittest.TextTestRunner()
      runner.run(suite())
  
imports: import unittest
  from igraph import hsv_to_rgb, hsva_to_rgba, hsl_to_rgb, hsla_to_rgba, rgb_to_hsl, rgba_to_hsla, rgba_to_hsva, rgb_to_hsv, GradientPalette, AdvancedGradientPalette
label_desc: Use image node_id 2 for calling a global function with example usage: test() without return types