def METHOD_NAME(chunks: chunk_map_type):
    (chunk_width, chunk_height) = (0, 0)
    for _, chunk_coords in chunks.items():
        this_chunk_width = chunk_coords[2] - chunk_coords[0]
        this_chunk_height = chunk_coords[3] - chunk_coords[1]
        chunk_width = max(chunk_width, this_chunk_width)
        chunk_height = max(chunk_height, this_chunk_height)
    return (chunk_width, chunk_height)