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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 isoformat(self):
 """Generate an ISO 8601 formatted time stamp. Returns: str: `ISO 8601`_ formatted time stamp .. _ISO 8601: http://www.cl.cam.ac.uk/~mgk25/iso-time.html """

        text = [self.strftime('%Y-%m-%dT%H:%M:%S'), ]
        if self.tzinfo:
            text.append(self.tzinfo.as_timezone())
        else:
            text.append('+00:00')
        return ''.join(text)