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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 _create_complete_graph(node_ids):
 """Create a complete graph from the list of node ids. Args: node_ids: a list of node ids Returns: An undirected graph (as a networkx.Graph) """

    g = nx.Graph()
    g.add_nodes_from(node_ids)
    for (i, j) in combinations(node_ids, 2):
        g.add_edge(i, j)
    return g