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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 _get_business_hours_by_sec(self):
 """ Return business hours in a day by seconds. """

        if self._get_daytime_flag:
            # create dummy datetime to calculate businesshours in a day
            dtstart = datetime(2014, 4, 1, self.start.hour, self.start.minute)
            until = datetime(2014, 4, 1, self.end.hour, self.end.minute)
            return (until - dtstart).total_seconds()
        else:
            dtstart = datetime(2014, 4, 1, self.start.hour, self.start.minute)
            until = datetime(2014, 4, 2, self.end.hour, self.end.minute)
            return (until - dtstart).total_seconds()