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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_time(self):
 """Increments the timestep counter by one. Furthermore ``self.time['days_elapsed']`` and ``self.time['num_steps_per_year']`` are updated. The function is called by the time stepping methods. """

        self.time['steps'] += 1
        # time in days since beginning
        self.time['days_elapsed'] += self.time['timestep'] / const.seconds_per_day
        if self.time['day_of_year_index'] >= self.time['num_steps_per_year']-1:
            self._do_new_calendar_year()
        else:
            self.time['day_of_year_index'] += 1