def check_in(position, info_pos_line_pairs):
    """
    Check if position corresponds to the starting position of a pair in info_pos_line_pairs
    (return pair if found, empty list otherwise)
    :param position: list
    :param info_pos_line_pairs: list of lists
    :return: list
    """

    # pos_pair form: [info, [in_line_position_1, line_number_1], [in_line_position_2, line_number_2]]
    for i in info_pos_line_pairs:
        if position[0] == i[1][0] and position[1] == i[1][1]:
            return i

    return []