def safety_check_first_line(first_line: str) -> None:
    """Inspects first line of lineage_notes.txt to perform safety check.

    We pull all of our Pango lineages from a human-edited .txt file.
    The format has been stable so far, but if things ever change significantly,
    the planned loading process will probably explode. In case of changes,
    we will need to investigate and alter the loading process.

    This check exists to avoid ever accidentally loading a file where the
    format has (probably) changed. Assumption is that if the first line has
    changed from what it used to be, the file format has probably changed.
    Will print the problem and raise an exception.

    Raises:
        RuntimeError -- If first line of file not what was expected.
    """
    EXPECTED_FIRST_LINE = "Lineage\tDescription\n"
    if first_line != EXPECTED_FIRST_LINE:
        print("First line of imported lineages file has changed!")
        print("Loading script was originally written for previous version.")
        print(f"Expected: '{EXPECTED_FIRST_LINE}'")
        print(f"Actually got first line: '{first_line}'")
        print("Very likely you need to rewrite loading script. Aborting.")
        raise RuntimeError("Format of lineage file has likely changed")
    return None