code: def colors(k):
      return [(255, 0, 0), (0, 255, 0), (0, 0, 255)][k % 3]
  
file_path: pyro/examples/air/viz.py
imports: import math
  from collections import namedtuple
  import numpy
  from PIL import Image, ImageDraw
label_desc: Use image node_id 4 for calling a global function with example usage: colors(k) and returns: list