<｜begin▁of▁sentence｜>### Instruction:
Given a tournament graph with edge set [(0, 1), (0, 2), (1, 2), (1, 3), (2, 3), (3, 0)], can you tell me if the tournament is strongly connected using NetworkX? Also, if we remove the edge (3, 0) and add an edge (0, 3), is it still strongly connected?
### Response:
import networkx as nx

# Create a tournament graph
G = nx.DiGraph([(0, 1), (0, 2), (1, 2), (1, 3), (2, 3), (3, 0)])

# Check if the tournament is strongly connected
is_connected = nx.tournament.is_strongly_connected(G)
print('Is the tournament strongly connected?', is_connected)

# Modify the graph to break the strong connectivity
G.remove_edge(3, 0)
G.add_edge(0, 3)

# Re-check if the tournament is strongly connected
is_connected = nx.tournament.is_strongly_connected(G)
print('Is the tournament strongly connected after modification?', is_connected)
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