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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 _next_month(self):
 """Update calendar to show the next month."""

        self._canvas.place_forget()

        year, month = self._date.year, self._date.month
        self._date = self._date + self.timedelta(
            days=calendar.monthrange(year, month)[1] + 1)
        self._date = self.datetime(self._date.year, self._date.month, 1)
        self._build_calendar()