def streets_per_node_proportions(G: nx.MultiDiGraph) -> dict[int, float]:
    """
    Calculate streets-per-node proportions.

    Parameters
    ----------
    G
        Input graph.

    Returns
    -------
    spnp
        Dictionary keyed by count of streets incident on each node, and with
        values of what proportion of nodes in the graph have this count.
    """
    n = len(G.nodes)
    spnc = streets_per_node_counts(G)
    return {i: count / n for i, count in spnc.items()}

    Calculate streets-per-node proportions.

    Parameters
    ----------
    G
        Input graph.

    Returns
    -------
    spnp
        Dictionary keyed by count of streets incident on each node, and with
        values of what proportion of nodes in the graph have this count.
    
osmnx/stats.py