add TimeStamp

import datetime

from astropy import time

def now():

    """ Return ISOT8601 format datetime, for time stamps in data products. """

def now_dfs():

    """ Return ISOT8601 format datetime, for DFS usage only. """

    return datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S')

class TimeStamp:

    def __init__(self, file_path=""):

        self.file_path = file_path

    def truncate(self):

        with open(self.file_path, 'w') as file:

            file.truncate(0)

    def punch_in(self):

        with open(self.file_path, "a+") as f:

            f.write(f"{time.Time.now().isot}+00:00\n")