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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 update_clock(self, dt):
 """This method is called by the ClockApp whenever the timer fires to update the clock. `dt` is a timezone-aware datetime object. """

        dt = dt.astimezone(self.tzinfo)
        fmt = "%H:%M"
        if self.show_seconds:
            fmt = "%H:%M:%S"

        self.time_txt.text = dt.strftime(fmt)

        suppl_text = "{0} {1}".format(dt.strftime("%Y-%m-%d"), self.timezone)
        self.suppl_txt.text = suppl_text

        self.viewer.redraw(whence=3)