def calculate_cut_coords_by_zoom(
        coord, metatile_zoom, cfg_tile_sizes, max_zoom):
    """
    Returns a map of nominal zoom to the list of cut coordinates at that
    nominal zoom.

    Note that max_zoom should be the maximum coordinate zoom, not nominal
    zoom.
    """

    tile_sizes_by_zoom = calculate_sizes_by_zoom(
        coord, metatile_zoom, cfg_tile_sizes, max_zoom)

    cut_coords_by_zoom = {}
    for nominal_zoom, tile_sizes in tile_sizes_by_zoom.iteritems():
        cut_coords = []
        for tile_size in tile_sizes:
            cut_coords.extend(metatile_children_with_size(
                coord, metatile_zoom, nominal_zoom, tile_size))

        cut_coords_by_zoom[nominal_zoom] = cut_coords

    return cut_coords_by_zoom
Returns a map of nominal zoom to the list of cut coordinates at that
    nominal zoom.

    Note that max_zoom should be the maximum coordinate zoom, not nominal
    zoom.