so attached, giving
        giving a full format of 'YYYY-MM-DD HH:MM:SS.mmmmmm+HH:MM'.

        Optional argument sep specifies the separator between date and
        time, default 'T'.

        The optional argument timespec specifies the number of additional
        terms of the time to include. Valid options are 'auto', 'hours',
        'minutes', 'seconds', 'milliseconds' and 'microseconds'.
        z