<｜begin▁of▁sentence｜>### Instruction:
Given the High-energy theory collaborations graph which you can read from a GML file named hep-th.gml, can you use the Louvain method in cdlib to perform community detection? And can you compute the modularity density of the detected communities?
### Response:
import networkx as nx
from cdlib import algorithms, evaluation

# Read the high-energy theory collaborations graph
G = nx.read_gml('hep-th.gml')

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

# Compute the modularity density
modularity_density = evaluation.modularity_density(G, communities)

# Print the modularity density score
print(modularity_density.score)
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