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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 age_simulants(self, event: Event):
 """Updates simulant age on every time step. Parameters event : An event object emitted by the simulation containing an index representing the simulants affected by the event and timing information. """

        population = self.population_view.get(event.index, query="alive == 'alive'")
        population['age'] += event.step_size / pd.Timedelta(days=365)
        self.population_view.update(population)