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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 merge(self, rule):
 """ Migrate all stateful attributes from the old rule """

        with self._lock:
            self._request_count = rule.request_count
            self._borrow_count = rule.borrow_count
            self._sampled_count = rule.sampled_count
            self._reservoir = rule.reservoir
            rule.reservoir = None