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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 limit(self, key):
 """ Function to log an event with the given key. If the ``key`` has not exceeded their alotted events, then the function returns ``False`` to indicate that no limit is being imposed. If the ``key`` has exceeded the number of events, then the function returns ``True`` indicating rate-limiting should occur. :param str key: A key identifying the source of the event. :returns: Boolean indicating whether the event should be rate-limited or not. """

        if self._debug:
            return False

        counter = self.database.List(self.name + ':' + key)
        n = len(counter)
        is_limited = False
        if n < self._limit:
            counter.prepend(str(time.time()))
        else:
            oldest = float(counter[-1])
            if time.time() - oldest < self._per:
                is_limited = True
            else:
                counter.prepend(str(time.time()))
            del counter[:self._limit]
        counter.pexpire(int(self._per * 2000))
        return is_limited