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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_state(self, index, event_time, population_view):
 """Moves a population between different states using information this state's `transition_set`. Parameters index : iterable of ints An iterable of integer labels for the simulants. event_time : pandas.Timestamp When this transition is occurring. population_view : vivarium.framework.population.PopulationView A view of the internal state of the simulation. """

        return _next_state(index, event_time, self.transition_set, population_view)