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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_average_time_stamp(action_set):
 """Return the average time stamp for the rules in this action set."""

        # This is the average value of the iteration counter upon the most
        # recent update of each rule in this action set.
        total_time_stamps = sum(rule.time_stamp * rule.numerosity
                                for rule in action_set)
        total_numerosity = sum(rule.numerosity for rule in action_set)
        return total_time_stamps / (total_numerosity or 1)