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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 make_flow_labels(graph, flow, capac):
 """Generate arc labels for a flow in a graph with capacities. :param graph: adjacency list or adjacency dictionary :param flow: flow matrix or adjacency dictionary :param capac: capacity matrix or adjacency dictionary :returns: listdic graph representation, with the arc label strings """

    V = range(len(graph))
    arc_label = [{v:"" for v in graph[u]} for u in V]
    for u in V:
        for v in graph[u]:
            if flow[u][v] >= 0:
                arc_label[u][v] = "%s/%s" % (flow[u][v], capac[u][v])
            else:
                arc_label[u][v] = None   # do not show negative flow arcs
    return arc_label