def METHOD_NAME(s: str) -> int:
    last_dot = s.rindex('.')
    zone_sep = s.index('Z') if 'Z' in s else s.index('+')
    decimals_str = s[last_dot:zone_sep]
    s_clean = s.replace(decimals_str, '')
    dt = parse_date(s_clean)
    # rounding discards nothing, just to int
    seconds = round(dt.timestamp())
    decimals_str = decimals_str.replace('.', '').ljust(9, '0')
    full_str = str(seconds) + decimals_str
    return int(full_str)