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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def is_intersection(g, n):
 """ Determine if a node is an intersection graph: 1 -->-- 2 -->-- 3 False graph: 1 -- 2 -- 3 | 4 True Parameters g : networkx DiGraph n : node id Returns ------- bool """

    return len(set(g.predecessors(n) + g.successors(n))) > 2