code: def test_graph():
      import geoplotlib
      from geoplotlib.utils import read_csv
  
      movement_data = read_csv("./data/graph_movement.csv")
  
      geoplotlib.graph(
          movement_data,
          src_lat="SourceLat",
          src_lon="SourceLon",
          dest_lat="TargetLat",
          dest_lon="TargetLon",
          alpha=80,
          linewidth=2,
          color="inferno",
          color_by="Weight",
          levels=10,
      )
  
      geoplotlib.show()
  
label_desc: Use image node_id 1 for calling a global function with example usage: test_graph() without return types