import datetime

t0 = datetime.datetime(year=1951, month=1, day=1, hour=0, minute=0, second=0, microsecond=0)
now_time = 290263084.07456899

def cal_rss_timestamp(offset_seconds) -> str:
    """Calculate RSS timestamp given offset in seconds from 1951-01-01 00:00:00.

    Args:
        offset_seconds (int): Number of seconds offset from the base time.

    Returns:
        str: Formatted timestamp string in 'YYYY-MM-DD HH:MM:SS' format.
    """
    target_time = t0 + datetime.timedelta(seconds=offset_seconds)
    return target_time.strftime("%Y-%m-%d %H:%M:%S")

def cal_launch_date_via_met(met):
    met_time = now_time - met
    return cal_rss_timestamp(met_time)

if __name__ == "__main__":
    print(cal_launch_date_via_met(23083334.171755522))
    print('done')

