<｜begin▁of▁sentence｜>### Instruction:
Given an undirected graph with edge set [(1, 2), (2, 3), (3, 4), (4, 1), (1, 3)], can you find the maximum clique using NetworkX?
### Response:
import networkx as nx
from networkx.algorithms import approximation as approx

# Create an undirected graph
G = nx.Graph()
G.add_edges_from([(1, 2), (2, 3), (3, 4), (4, 1), (1, 3)])

# Find the maximum clique
max_clique_set = approx.max_clique(G)

print('The maximum clique of the graph:', max_clique_set)
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