def split_title(title, delim):
    """Return largest title piece."""
    largest_len = 0
    largest_piece = None
    piece_len = 0
    for piece in title.split(delim):
        piece_len = len(piece)
        if piece_len > largest_len:
            largest_len = piece_len
            largest_piece = piece
    return largest_piece or title
