<｜begin▁of▁sentence｜>### Instruction:
Given the Power Grid Graph which you can read from a gml file named power.gml, can you use the Louvain method in cdlib to perform community detection? And can you compute the modularity density to evaluate the quality of the detected communities?
### Response:
import networkx as nx
from cdlib import algorithms, evaluation

# Load the Power Grid graph
G = nx.read_gml('power.gml')

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

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

# Print the Modularity Density result
print('Modularity Density:', mod_density.score)
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