def _datetime_to_str(dt):
    """Convert datetime object to camtasia lastMod format.

    <year><month><day>T<hour><minute><second>, e.g. 20190606T103830
    """
    return (
        f'{dt.year}{dt.month:02}{dt.day:02}T{dt.hour:02}{dt.minute:02}{dt.second:02}'
        )
