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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 end_experience_collection_timer(self):
 """ Inform Metrics class that experience collection is done. """

        if self.time_start_experience_collection:
            curr_delta = time() - self.time_start_experience_collection
            if self.delta_last_experience_collection is None:
                self.delta_last_experience_collection = curr_delta
            else:
                self.delta_last_experience_collection += curr_delta
        self.time_start_experience_collection = None