def is_simplified(G):
    """
    Determine if a graph has already had its topology simplified. If any of its edges have a
    geometry attribute, we know that it has previously been simplified.

    Parameters
    ----------
    G : graph

    Returns
    -------
    bool
    """
    edges_with_geometry = [d for u, v, k, d in G.edges(data=True, keys=True) if 'geometry' in d]
    return len(edges_with_geometry) > 0