<｜begin▁of▁sentence｜>### Instruction:
Given the graph of books about US politics which you can read from a GML file named polbooks.gml, can you use the Louvain method in cdlib to perform community detection and then compute the average transitivity of nodes within the detected communities? You need to print the average transitivity score of those communities.
### Response:
import networkx as nx
from cdlib import algorithms, evaluation

# Create a graph
G = nx.read_gml('polbooks.gml')

# Detect communities using the Louvain method
communities = algorithms.louvain(G)

# Compute the average transitivity for the detected communities
avg_transitivity_score = evaluation.avg_transitivity(G, communities)

print(avg_transitivity_score.score)
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