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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 add_graph(patterns, G):
 """Add a graph to a set of unique patterns."""

    if not patterns:
        patterns.append([G])
        return
    for i, graphs in enumerate(patterns):
        if networkx.is_isomorphic(graphs[0], G, node_match=type_match,
                                  edge_match=type_match):
            patterns[i].append(G)
            return
    patterns.append([G])