<｜begin▁of▁sentence｜>### Instruction:
Given the Political blogs Graph which can be read from a GML file named polblogs.gml, can you use the Louvain method in cdlib to perform community detection and then compute the Modularity Density of the discovered community structure?

Notes: You need to print the Modularity Density score.
### Response:
import networkx as nx
from cdlib import algorithms, evaluation

# Read the graph structure from a gml file
G = nx.read_gml('polblogs.gml')

# Perform community detection using the Louvain method
communities = algorithms.louvain(G)

# Calculate the Modularity Density
mod_density = evaluation.modularity_density(G, communities)

print(mod_density.score)
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