def get_num_signs(gt):
    """count number of signs.

    Args:
        gt: list of framewise labels/ predictions.

    Returns:
        number of signs
    """
    item_old = gt[0]
    count = 0
    for ix, item in enumerate(gt):
        if item_old == 0 and item == 1:
            count += 1
        if ix == len(gt)-1 and item != 1:
            count += 1

        item_old = item
    return count