def METHOD_NAME() -> None:
    """
    Compute structural diffs between hard forks.
    """
    import shutil
    import sys
    input_path = sys.argv[1]
    output_path = sys.argv[2]
    shutil.rmtree(output_path, ignore_errors=True)
    os.makedirs(output_path)
    forks = Hardfork.discover()
    index_path = os.path.join(output_path, "index.rst")
    with open(index_path, "w") as f:
        f.write("===========\n")
        f.write("Comparisons\n")
        f.write("===========\n\n")
        f.write(".. toctree::\n")
        f.write("   :maxdepth: 1\n\n")
    for o, n in window(forks):
        diff(output_path, input_path, o, n)