def test_breadth_search():
graph = Graph()
node1 = graph.add_node('Pandora')
node2 = graph.add_node('Aredelle')
node3 = graph.add_node('Metroville')
node4 = graph.add_node('Monstarpolis')
node5 = graph.add_node('Narina')
node6 = graph.add_node('Naboo')
graph.add_edge(node1, node2)
graph.add_edge(node2, node3)
graph.add_edge(node2, node4)
graph.add_edge(node3, node5)
graph.add_edge(node3, node6)
graph.add_edge(node4, node6)
assert graph.breadth_search(node1) == [
'Pandora', 'Aredelle', 'Metroville', 'Monstarpolis', 'Narina', 'Naboo'
]
