<｜begin▁of▁sentence｜>### Instruction:
Given a NetworkX graph representing a social club's member interactions, how would you use the greedy_modularity_communities function to detect communities within the graph? Additionally, provide a JSON formatted string representing members of the first detected community.
### Response:
from networkx.algorithms.community import greedy_modularity_communities
import networkx as nx
import json

# Create a graph
g = nx.karate_club_graph()

# Detect communities in the graph using NetworkX
communities = list(greedy_modularity_communities(g))

# Retrieve specific community based on its index, for example, the first community
first_community = communities[0]

# Convert the set to a list for JSON serialization
first_community_list = list(first_community)

# Generate a JSON object containing the first community
json_object = json.dumps({'first_community': first_community_list}, indent=4)
print(json_object)
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