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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 parse_isoformat(timestamp):
 """Parse an ISO 8601 formatted time stamp. Args: timestamp (str):
 Timestamp to parse Returns: Timestamp: Parsed timestamp """

        if len(timestamp) == 20:
            zone = TzOffset('+00:00')
            timestamp = timestamp[:-1]
        elif len(timestamp) == 24:
            zone = TzOffset('%s:%s' % (timestamp[-5:-2], timestamp[-2:]))
            timestamp = timestamp[:-5]
        elif len(timestamp) == 25:
            zone = TzOffset(timestamp[-6:])
            timestamp = timestamp[:-6]
        timestamp = Timestamp.strptime(timestamp, '%Y-%m-%dT%H:%M:%S')
        timestamp = timestamp.replace(tzinfo=zone)
        return timestamp