<｜begin▁of▁sentence｜>### Instruction:
Given a graph with the edge set [('A', 'B'), ('B', 'C'), ('D', 'E'), ('E', 'F'), ('E', 'G'), ('F', 'G')], how can you generate a sequence of nodes following the depth-first search (DFS) strategy where for each node except the first, at least one neighbor appeared earlier in the sequence?
### Response:
import networkx as nx

# Create a graph
G = nx.Graph()
G.add_edges_from([('A', 'B'), ('B', 'C'), ('D', 'E'), ('E', 'F'), ('E', 'G'), ('F', 'G')])

# Generate nodes in a sequence given by a depth-first traversal
sequence = list(nx.strategy_connected_sequential_dfs(G))

print('DFS traversal sequence:', sequence)
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