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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_cyclic(graph):
 """ Return True if the directed graph g has a cycle. The directed graph should be represented as a dictionary mapping of edges for each node. """

    path = set()

    def visit(vertex):
        path.add(vertex)
        for neighbour in graph.get(vertex, ()):
            if neighbour in path or visit(neighbour):
                return True
        path.remove(vertex)
        return False

    return any(visit(v) for v in graph)