<｜begin▁of▁sentence｜>### Instruction:
As a commercial pilot, you often have to navigate through various airports and airspaces. To ensure the safety and efficiency of your flights, you need to identify potential points of congestion or disruption in the airspace. Using the networkx library, you can analyze the structure of the airspace graph to locate critical points known as articulation points, which could impact the flow of air traffic. By identifying these points, you can effectively plan routes and make informed decisions to optimize the flight path and maintain air traffic control efficiency.
### Response:
import igraph as ig

# Read a graph from a file
g = ig.read('graph_data.gml')

# Find the articulation points in the graph
articulation_pts = g.articulation_points()

# Print the articulation points
print('Articulation points:', articulation_pts)
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