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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def is_expired(self, time_offset_seconds=0):
 """ Checks to see if the Session Token is expired or not. By default it will check to see if the Session Token is expired as of the moment the method is called. However, you can supply an optional parameter which is the number of seconds of offset into the future for the check. For example, if you supply a value of 5, this method will return a True if the Session Token will be expired 5 seconds from this moment. :type time_offset_seconds: int :param time_offset_seconds: The number of seconds into the future to test the Session Token for expiration. """

        now = datetime.datetime.utcnow()
        if time_offset_seconds:
            now = now + datetime.timedelta(seconds=time_offset_seconds)
        ts = boto.utils.parse_ts(self.expiration)
        delta = ts - now
        return delta.total_seconds() <= 0