def random_weighted_graph(n,p,lb,up):
#NAME: random_weighted_graph
#DESCRIPTION: produces a random weighted graph on n vertices
#INPUT: n = number of vertices
#       p = probability an edge exists between two vertices
#       lb = lower bound on edge weights
#       ub = upper bound on edge weights
#OUTPUT: GG = Weighted Grapgh
#EXAMPLE: GG = random_weighted_graph(6,.4,1,20)
    import random
    G = graphs.RandomGNP(n,p);   # creates unweighted random graph
    m = G.size();                             # m is the number of edges in graph
    uw_edges = G.edges();
    w_edges = [(uw_edges[i][0], uw_edges[i][1], random.randint(lb,up)) for i in range(0,m)]
    GG = Graph(w_edges, weighted=true)
    GG.show(edge_labels=true)
    return GG


random_weighted_graph(10,.4,2,10)