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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 get_graph_component(graph):
 """ Identify strongly connected components in a graph using Tarjan's algorithm. graph should be a dictionary mapping node names to lists of successor nodes. """

    components = map(partial(_visit, graph=graph), graph)
    node_component = dict(_gen_node_component(components))
    graph_component = {component: [] for component in components}
    graph_component.update(
        dict(_gen_graph_component(graph, node_component, _gen_graph_value)))

    return graph_component