from typing import List


def fix_survey_timings(header: bytes, rows_list: List[List[bytes]], file_path: str) -> bytes:
    """ Survey timings need to have a column inserted stating the survey id they come from."""
    survey_id = file_path.rsplit("/", 2)[1].encode()
    for row in rows_list:
        row.insert(2, survey_id)
    header_list = header.split(b",")
    header_list.insert(2, b"survey id")
    return b",".join(header_list)