<｜begin▁of▁sentence｜>### Instruction:
As a Senior Network Analyst at a tech consultancy firm, you have been tasked with optimizing the efficiency of communication within a large organization. You have access to a graph data file named "adjnoun.gml" that represents the connections between various departments in the company. Using the Girvan–Newman algorithm available in the cdlib library, you are required to conduct community detection in the network to identify optimal groupings of departments based on their interactions. Additionally, you need to generate a JSON representation of the detected communities for further analysis and decision-making.
### Response:
import networkx as nx
from cdlib import algorithms

# Load a graph
G = nx.read_gml('adjnoun.gml')

# Apply Girvan-Newman algorithm to detect communities
communities = algorithms.girvan_newman(G, level=1)

# Generate JSON representation of the communities
communities_json = communities.to_json()

print(communities_json)
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