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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 add(self, count, timestamp=None):
 """Add a value at the specified time to the series. :param count: The number of work items ready at the specified time. :param timestamp: The timestamp to add. Defaults to None, meaning current time. It should be strictly greater (newer) than the last added timestamp. """

        if timestamp is None:
            timestamp = time.time()
        if self.last_data >= timestamp:
            raise ValueError("Time {} >= {} in load average calculation".format(self.last_data, timestamp))
        self.last_data = timestamp

        for meta in self.intervals.values():
            meta.push(count, timestamp)