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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 set_display_mode(self, mytz, fmt):
 """Set the display mode for self. :arg mytz: A pytz.timezone object. :arg fmt: A format string for strftime. ~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~- PURPOSE: Modifies self.display_timestamp to first parse self.timestamp and then format according to given timezone and format string. """

        my_stamp = dateutil.parser.parse(self.timestamp)
        tz_stamp = my_stamp.astimezone(
            mytz) if my_stamp.tzinfo is not None else my_stamp
        self.display_timestamp = tz_stamp.strftime(fmt)