4907.sagews

A = Graph()
B = Graph()

A.add_vertices([1, 2, 3])

B.add_vertices([1, 2, 3])

A.add_edge(1, 2)
B.add_edge(1, 2)

A.is_subgraph(B)

True

B.add_edge(1, 3)

A.is_subgraph(B)

False