code: def main():
      # Create Network instance
      network = Network()
  
      # Add three TestNode regions to network
      network.addRegion("region1", "TestNode", "")
      network.addRegion("region2", "TestNode", "")
      network.addRegion("region3", "TestNode", "")
  
      # Set dimensions on first region
      region1 = network.getRegions().getByName("region1")
      region1.setDimensions(Dimensions([1, 1]))
  
      # Link regions
      network.link("region1", "region2", "UniformLink", "")
      network.link("region2", "region1", "UniformLink", "")
      network.link("region1", "region3", "UniformLink", "")
      network.link("region2", "region3", "UniformLink", "")
  
      # Initialize network
      network.initialize()
  
      # Initialize Network Visualizer
      viz = NetworkVisualizer(network)
  
      # Render w/ graphviz
      viz.render(renderer=GraphVizRenderer)
  
      # Render w/ networkx
      viz.render(renderer=NetworkXRenderer)
  
      # Render to dot (stdout)
      viz.render(renderer=DotRenderer)
  
      # Render to dot (file)
      viz.render(renderer=lambda: DotRenderer(open("example.dot", "w")))
  
label_desc: Use image node_id 1 for calling a global function with example usage: main() without return types